Last night (NZT), Mr Pownall carried on questioning Vincent's version of events, which he labelled "absurd".
Vincent had earlier given evidence about meeting a man called Varun Gandhi in a hotel room, booked by Gandhi, to discuss a sponsorship deal.
When he arrived, there was no cricket equipment with Gandhi - only a woman.
After 15 minutes or so, Vincent said Gandhi offered him money and a woman as a "gift" in return for help to fix matches for the Chandigarh Lions.
Vincent said he told his agent, Leanne McGoldrick, that he left the money inside the safe in Gandhi's room, refused the services of the woman and left.
He also told investigators from the International Cricket Council that he refused the money and the woman.
It wasn't until Vincent was interviewed by the Met Police that he told the full truth - he had sex with the woman before he left the room.
Vincent said he omitted the sexual encounter from his original statement to the ICC because he was worried about damaging his already fragile relationship with his former wife, Eleanor Riley.
"My relationship with my ex-wife isn't a healthy one, we've got two young girls, I've inflicted a lot of damage."
At this point, he went quiet and struggled to answer.
"Can I help you?" asked Mr Pownall, to which Vincent replied, "No, you can't".
"In terms of the cricket side of the fixing, I opened everything up. At the time [of the ICC statement] my relationship with my ex was horrendous, I was trying to be a father at the same time," said Vincent.
"I didn't want to make matters worse."
Vincent later disclosed the sexual encounter to his legal team and the Met Police, who were by then investigating Cairns.
"There could have been hidden cameras in the room for blackmailing, I had to disclose my disgusting behaviour," said Vincent.
"My heart and soul is out there. I'm ashamed of what I did. Also not disclosing [what happened]. But I hope you can understand the reasons why [I didn't]."
At this point, Vincent implored Mr Justice Sweeney to intervene in Mr Pownall's line of questioning.
The QC halted, but not before suggesting that Vincent only disclosed the sexual encounter because he was worried potential footage from hidden cameras might disclose other lies about the meeting with Gandhi.
"I've never lied to the Met Police. That was my reason in disclosing everything, so I wouldn't be sitting here and you would bring a photograph out."
The corrupt approach is important to the case because Vincent alleges Cairns told him "You work for me now" after he told Cairns about Gandhi.
- by Jared Savage in London
