The paper revealed that Michelle Young had hired Simon Sutton, described as "a controversial fraud investigator".
The Mail says Young was particularly paranoid about enquiries on his wealth. He had stated that the hunt for the money was driving him crazy, and he had even demanded to be confined for treatment under the Mental Health Act.
In one of Britain's biggest divorce cases, Michelle had hired up to eight private detectives to search for her husband's assets, according to the Daily Mail.
The case has seen several twists although Scotland Yard has said the death is not considered suspicious.
According to a friend, Young was being tracked by the Russian and Turkish mafia after some property investment deals had turned into nothing and left him broke.In the divorce trial, Young had repeatedly claimed he was not able to pay the maintenance fee to his former wife and daughters, although the judge in charge convicted him for contempt of court for hiding his assets from the inquiry.
In 2013, Young spent six months in prison for that sentence.
Although Young's friends have claimed that he would have never committed suicide, Scotland Yard is under pressure to open an inquiry after The Telegraph revealed that four of his friends and business associates have also died in mysterious circumstances in the last four years.
The group included the exiled oligarch Boris Berezovsky, who was found hanging in his Surrey house in 2013.