Mr Denis O'Brien's former accountant, Mr Aidan Phelan, denied getting involved in business deals as a way of providing financial assistance to Mr Michael Lowry.
Mr John Coughlan SC, for the tribunal, put it to Mr Phelan that a £420,000 sterling property deal in Cheadle was one of a series of transactions after a previous attempt to pass money to the former minister for communications failed.
In 1996 money intended for Mr Lowry "got stuck with an intermediary", Mr Coughlan said. He put it to Mr Phelan that what Mr O'Brien construed as a legitimate house purchase in Spain was in fact a failed attempt to give funds to Mr Lowry.
"Something had to be done. Mr Lowry continued to need assistance, and that's why you got involved with him in relation to these transactions," Mr Coughlan said.
Mr Phelan denied the accusations. "It doesn't look like that to me at all," he said.
He said Mr Lowry was "a decent man" who deserved a chance to do business.
"He's not a leper or an AIDS victim," Mr Phelan said. He immediately apologised for the remark.
Mr Coughlan put it to Mr Phelan that he had attempted to deliberately mislead Investec Bank, which lent the money for the Cheadle deal, by omitting references to Mr Lowry in two letters examined by the tribunal yesterday.
The first, written by Mr Phelan's English solicitor, Mr Christopher Vaughan, at Mr Phelan's request, set out a "purported" history of the transaction, according to Mr Coughlan.
"Would you not agree, Mr Phelan, that this letter is completely misleading as a true history of this transaction?" Mr Coughlan asked.
Mr Phelan replied: "I don't think it's completely misleading. I think there are gaps."
He said he could not speak for Mr Vaughan.
Mr Vaughan, who has represented Mr O'Brien as well as Mr Phelan, has informed the tribunal he will not be co-operating with its inquiry.
After meeting the tribunal's legal team, he said in a letter received by the tribunal yesterday that he did not intend to give evidence. However, Mr Phelan said he was anxious that the solicitor could yet be persuaded to participate in proceedings.
A second letter to an Investec Bank official was also examined yesterday.
Mr Phelan said he had a meeting with a senior executive at the bank, Mr Michael Cullen, when Mr Cullen found out Mr Lowry was involved in the transaction. This happened after his meeting with bank officials on February 28th of this year. Mr Phelan agreed that Mr Cullen was concerned about Mr Lowry's involvement.
During that meeting, Mr Phelan said, Mr Cullen told him the bank "didn't want to know" about Mr Lowry's company, Catclause Ltd. Mr Phelan said Mr Cullen wanted him to write a letter to the bank about the matter.
"He described the letter I should write to the bank. He dictated it," he said.
Mr Phelan said the letter sent to another senior Investec Bank executive, Mr Tony Morland, in March of this year was "more or less" as dictated by Mr Cullen. The letter contained no reference to Mr Lowry and indicated Mr Phelan was the person involved in the transaction from the beginning.
Mr Phelan said he then went to Canada and, on his return to Ireland, learned that the matter had been referred to the Central Bank and, subsequently, the tribunal.