From what I gather, O'Leary has no say in whether Hitz stays or not, thats all down to contract stuff. Expect to see him start a fair few games during the run in, if only to tie up a valuable asset to a long contract so we don't see him dissapear for peanuts.
Berson is a strange one. I would speculate he doesn't get on with either his team mates or O'Leary. There can be no other logical explanation. I think he'll stay though.....