Former Tottenham and Portsmouth player O'Hara was criticised by some Wolves supporters during last season's Championship campaign, but he recently denied that he had been on trial at Queen's Park Rangers.
Roger Johnson and Stephen Ward were among a group of players, including O'Hara, who were told by boss Kenny Jackett they were no longer wanted by the club this summer.
"I feel for those (transfer listed) lads," Jackett told the Birmingham Mail after the Under 21 game against Everton.
"If they can get some game-time in the run-up to the window closing they then have the opportunity to phone around and phone their agents and let people come and watch them.
"The scouts requests for the game were really, really high. I don't know if he (O'Hara) is the reason, the amount of clubs that come and watch these games on a regular basis is very, very high anyway."