I don't know who I suspect, but I doubt it's Andrew, because I don't think Big Brother or CBS really wants to make the contestant who's most obviously identifying himself as religious the saboteur. The grief they could potentially get for that would likely make them think twice. Besides, Andrew's being way too obvious--choosing to sit out the first challenge, for instance. Someone who was really trying to make it until the fifth week wouldn't want to draw that much attention to himself/herself too early.
That being said, I always think it's a little silly when competitors in something like Big Brother or Survivor go out of their way to make a point about how they would never do anything during the game that would violate their religious beliefs. Virtually all organized religions involve some version of the golden rule and tenets against things like lying, and the vast majority of the competitors in such games don't abide by such rules, not if they want to win. Heck, Andrew didn't even make it out of the first episode without lying--he didn't admit he was a doctor and when he saw Britney writhing in pain, he said he wanted to do something about it, but he didn't want to blow his cover. I'm pretty sure Judaism wouldn't exactly encourage either of those actions.