Evangelist Tony Anthony's fall two years ago was as dramatic as his ascent.

His 2004 book Taming the Tiger was the Christian publishing sensation of the decade. It purported to be Anthony's account of his early life and training as a Kung Fu expert, his work as a close protection personal security guard, his criminal activity and conversation to Christianity. The dramatic story of redemption was taken to the heart of evangelical Christians and is said to have sold more than 1.5 million copies in 25 countries (though large numbers were bought by Anthony's own ministry to be distributed during his campaigns).

However, the book was investigated by an independent Evangelical Alliance-appointed panel in 2013, and found to be largely fictional. Anthony's credibility was destroyed.

Investigators found that large parts of the book never happened. Anthony wasn't a kung fu champion. Descriptions of Kung Fu techniques appeared to be copied from a website. Despite his claims to have grown up partially in China, he couldn't recognise Chinese script. His claims to have worked for a senior Saudi diplomat didn't stack up and neither did his accounts of hazardous close-protection security work.

But now he's back – and so is Taming the Tiger. Anthony has continued an evangelistic ministry with speaking engagements in the UK and abroad, and his book has just been republished.

So how has a book of which an independent panel said that "large sections" were untrue come to be been reissued as fact, and has anything changed?

The investigation arose after one of the directors of Anthony's evangelistic organisation, Avanti Ministries, resigned from his position when his attempts to get proof of the book's claims failed, subsequently forming an investigative group – the "Research Group" – with others who had similar concerns. They presented their findings to the Evangelical Alliance, which asked three senior members of its council to launch an independent investigation with the agreement of Avanti.

In a joint press release with Avanti in July 2013, the EA said that "large sections of the book Taming the Tiger, and associated materials, which claim to tell the true story of Tony Anthony's life, do not do so".

The two organisations said: "Both the Evangelical Alliance and Avanti Ministries take serious note of the findings of the report and as a result Avanti has concluded that it is not appropriate to continue to support Taming the Tiger."

Authentic Media, Anthony's publisher, announced it was withdrawing his materials from sale. However, Avanti Ministries – which subsequently closed – refused to agree to the publication of the report and in spite of its joint statement with the EA, continued to back Anthony, leading the Alliance to terminate Avanti's membership in September 2013. The whole story was written up extensively by Christian journalist Gavin Drake.

Anyone would imagine that this was the end of the story – a troubling tale of an evangelist gone bad, another casualty of spiritual warfare.

It didn't happen that way. Anthony, though bruised from the controversy, continued to affirm the substantial truth of his account and continued his speaking ministry. He attracted supporters who have created websites claiming to answer the charges against him, notably For The Sake Of The Gospel, whose author Ian Bruce is convinced of his truthfulness – and has taken over the former Avanti website – and the anonymous Framing the Tiger. Another website, The Way, ran an article accusing Anthony's critics of mounting a malicious personal vendetta against him.

And now Taming the Tiger has been released again. It has been lightly edited, but remains essentially the same story.

Publisher Richard Roper, whose business partner Jim Penberthy is a trustee of The Way, told Christian Today that he had been unaware of the controversy surrounding the book when it first came to him. He said that the first edition continued various errors, but that many of these were the responsibilities of the editor. More fundamentally, he argued that critics were mistaking the book's character: it was not a sober autobiography. Instead, "Large parts of the book are styled in a manner to present the gospel or to answer potential objections to the gospel. They use Tony's life experiences as background or medium for the message but for the purpose of presenting Christ."

He concluded that there were lots of allegations with little substance to them and that a "new and better" edition was justified.

That's not a conclusion shared by those who worked on Anthony's case. At issue is still the question of Anthony's basic truthfulness. When Avanti refused to agree to the publication of its joint report with the EA, the Research Group asked for the findings to be made public regardless. While this was not possible, its chair John Langlois issued a strongly-worded response, saying: "A day or so after the Report was delivered to Avanti they announced that Avanti was ceasing all operations. The office was closed and the telephone was cut off. We were informed that all communication had to be through Avanti's solicitor, Mr Duncan Elson, Head of Litigation & Dispute Resolution, at Charles Russell LLP.

"I was shocked that the directors of a charity registered with the Charity Commissioners – indeed any charity or any company, let alone a Christian ministry – would do this. I asked myself 'How will the supporters of Avanti know what is going on? How will financial supporters ever know how their money has been spent? How will they ever get to know the truth?'"

He reiterates the panel's conclusions that Anthony never went to China as a child as he claimed, was never involved in Kung Fu as he claimed and was never involved in close protection as he claimed. He added: "There are other more serious things in the report than those I have stated above."

Langlois told Christian Today that the panel "had no hesitation in concluding that Tony Anthony's life has been and continued to be dominated by lies".

He continued: "Any reader of the new edition should bear in mind while reading it that this is not a true story with some artistic licence. It is a work of fiction with a few facts woven in. Tony Anthony was not brought up in China. He was never a Kung Fu champion."

Though the original book is more than 10 years old, this is far from being ancient history – and doubts continue to circulate about Anthony's accounts of more recent events too.

Last July, he posted on his blog a description of a Christian Union event at London's Royal Holloway University. It's a moving account of how he spoke to an audience of around 400, many of whom were in tears at his testimony. He gave an invitation to come forward in response and says that there were "only 20 or 30 students that did not leave their chairs. The rest came to the front of the lecture hall when I invited them." The CU, he said, had only prepared 50 follow-up packs so "we had to think quick on our feet and make sure we took everyone's contact details".

The trouble is that the Royal Holloway CU have no knowledge of any such event ever having taken place. It did not organise the meeting and said that it was unlikely it took place as it would have been during graduation week.

A spokeswoman for UCCF, which co-ordinates CU work in British universities, told Christian Today: "I can confirm that the Christian Union at Royal Holloway did not organise this meeting and that they have never had any involvement with Tony Anthony. This was confirmed by the president of the CU at the time."

Christian Today spoke to Anthony about the new edition of the book and about the Royal Holloway story, which was removed from his website immediately after the interview. He said that he had been to Royal Holloway several times for events and that the July 2014 meeting was organised by an "independent Christian group hiring one of the meeting rooms", not by the CU – though in the article he specifically references the CU.

Of the new Taming the Tiger, Anthony said that he had gone through it carefully with editors – one of whom, Angela Little, had been his ghost-writer when the book was published by Authentic – and taken out errors such as the date of his conversion, typographical errors and "things which were worded clumsily and left me fair game" for critics. Aside from that, the substance of the book was the same, he said.

Anthony is clearly a polarising figure. For his supporters – and there are more than a few – he has been been the victim of a great wrong perpetrated by people using a few stray anomalies to undermine a fruitful gospel ministry. For the majority, the holes in his story are simply too big for him to retain his credibility as an evangelical Christian witness.

Anthony has so far refused to engage with his critics. He told Christian Today that it was "not down to me" to answer them. But he must realise that unanswered questions – and none of the original researchers are convinced by the material produced by his supporters – are not going to go away. An authoritative verdict was pronounced against Taming the Tiger in July 2013. It is hard to see what has changed since.

Follow @RevMarkWoods on Twitter.