On paper, Joseph Mifsud – who has emerged as a central figure in the criminal investigation into possible collusion between the Kremlin and the Trump campaign – looks like a seasoned professional in diplomacy and academia.

A fawning profile published in 2014 described the Malta native as a top former government official who helped negotiate his country’s entry into the European Union and later became head of the “venerable” London Academy of Diplomacy.

But a closer look at Mifsud’s record raises more questions than answers about the man who federal investigators now say told a young Trump campaign adviser that the Kremlin had “dirt” on Hillary Clinton. Evidence has also emerged that suggests Mifsud has a relationship with at least one senior Russian official in London.

Mifsud is not named in court documents released on Monday, which describe how the campaign aide, George Papadopoulos, lied to investigators about his contacts with “foreign agents”. But his biography and movements between Rome, London and Moscow, match those of the unnamed “professor” described in the court documents. On Tuesday, he acknowledged to the Daily Telegraph that he was the man described in the papers, but denied any wrongdoing, or knowledge of the Clinton emails.

The court documents paint him as a stealthy operator with links deep inside the Kremlin. While initially uninterested in Papadopoulos, Mifsud’s attitude changed once he learned that Papadopoulos was working for the Trump campaign, the documents say.

Court documents say that after their initial meeting in Rome, the pair met for breakfast in London, where Mifsud introduced Papadopoulos to an unidentified Russian national who he claimed – falsely – was Putin’s niece. Mifsud told the Telegraph that this allegation was untrue.

It is not clear whether details of these exchanges were shared with then-candidate Trump, but at a 31 March meeting he attended with the future president, Papadopoulos boasted that he had “connections” that could help facilitate a meeting with Putin.

Mifsud then allegedly traveled to Moscow, met Russian senior government officials, and then told Papadopoulos that the Kremlin was sitting on “thousands” of Clinton’s emails, the documents say.

In August, Mifsud told the Washington Post that he had “absolutely no contact” with the Russian government. “I am an academic, I do not even speak Russian,” he wrote.

But there is independent evidence of Mifsud’s links to Russia, including a photograph of him and Russia’s ambassador to London taken at the ambassador’s residence in May 2014. The caption says the two discussed an academic summit in Moscow that Mifsud had attended and British-Russia relations.

Attempts by the Guardian to reach Mifsud on a London mobile phone and in Rome were not successful.

Asked if Mifsud had ever served as a diplomat for the country, Malta’s ministry of foreign affairs did not respond to requests for comment. The Malta Times reported that Mifsud once worked for the former foreign minister, Michael Frendo.

George Papadopoulos, second from left, in a photograph released on Donald Trump’s Instagram account last year. Photograph: AFP/Getty Images

Today, there is no sign of the London Academy of Diplomacy on Middlesex Street in London. Phone numbers for the organisation that can be found online do not work and websites lead to error messages. A receptionist at the address said the organisation left the premises six months ago.

“Any stuff we get, we just send it back,” she said.

There are still some remaining traces of the academy, though, including a photograph of Mifsud and a senior representative of Russia’s embassy in London, a counsellor named Ernest Chernukhin, during a visit to the University of East Anglia. In the photograph, Mifsud is wearing a medal. The picture was taken on 10 July 2017.

The University of East Anglia, which has been linked to LAD in press reports, said the university used to validate LAD degree courses, but ended the arrangement in January 2014. A spokesperson said that Mifsud had an honorary professorship at the university from August 2013 to July 2016, a period in which Mifsud was allegedly in close contact with Papadopolous.

Another university, the University of Stirling, said Mifsud had been working as a full-time professorial teaching fellow in the politics department since May 2017, but declined to answer other questions.

Mifsud’s professional activities are not limited to the UK. In Rome, he is an official at Link Campus University, which is headed by a former Italian interior minister named Vincenzo Scotti.

One Rome-based professor claimed Link Campus had a reputation for being closely connected to some elements within the Italian intelligence services.

“Mifsud is a person who collaborates with us,” said one person who was reached at Link Campus.