Two BBC whistleblowers who tried to highlight the deceitful methods employed by Martin Bashir to obtain his explosive interview with Diana, Princess of Wales, have attacked the corporation’s “generic” apology.

Graphic designer Matt Wiessler, who was commissioned by Bashir to create mocked-up documents, has long claimed he was made the scapegoat for the scandal.

The report by Lord Dyson, former master of the rolls and head of civil justice, which was published on Thursday, found Bashir “deceived” Diana into agreeing to the interview.

The journalist commissioned falsified documents purporting to show payments into the bank account of Alan Waller, a former employee of Earl Spencer; Patrick Jephson, Diana’s private secretary; and Richard Aylard, private secretary to the Prince of Wales, the report found.

The documents falsely suggested the individuals were being paid for keeping the princess under surveillance.

Mr Wiessler said on Friday that his business had folded as a result of being blacklisted by the BBC, after blowing the whistle on Bashir’s tactics.

He told the Today programme: “Only under duress do we get some sort of apology and some sort of acknowledgement.”

Mr Wiessler said all he had received was a “well-crafted letter” from the BBC at 10pm on Thursday which did “the absolute minimum” to acknowledge how poorly he had been treated.

He added: “It’s just really weak, calculating and, quite honestly, after 25 years, it’s nasty what they are doing to this day.”

Mr Wiessler accused Bashir of “arrogance” for saying recently he is still proud of the Diana interview.

Former Panorama producer Mark Killick, who was sacked from the programme within 24 hours when he raised concerns, called Bashir a “dishonest reporter” who “lied and lied”.

Speaking to BBC Breakfast, he said: “I think (the report) makes it very clear that Martin Bashir was a dishonest reporter, that he not only forged a number of documents, but he lied and lied.”

Mr Killick said senior managers at the BBC had fostered a “culture of fear” to deter whistleblowers and orchestrated a smear campaign against its own employees.

“I was told we only want the loyal people on the programme – I had been on Panorama for 10 years – and I was effectively let go,” he said.

“That is what happened to whistleblowers at that time.”

Mr Killick criticised the BBC for its inadequate and “generic” apology to both whistleblowers and Diana’s sons.

“Many people, both on the Princess Diana side of the line and in the BBC, had their reputations destroyed by a smear campaign authorised by BBC senior management, and many of them lost their jobs,” he said.

“I’m not quite sure that a generic apology in the form of a press statement by the BBC is anything like adequate.”

He continued: “The culture of fear that was established then, it was a long time ago, but they sent a clear message to everyone in the BBC, ‘do not refer up, do not bring the BBC bad news’.”

Lord Dyson’s report said: “By showing Earl Spencer the fake Waller and Jephson/Aylard statements and informing him of their contents, Mr Bashir deceived and induced him to arrange a meeting with Princess Diana.

“By gaining access to Princess Diana in this way, Mr Bashir was able to persuade her to agree to give the interview.”