In general you should spend less time figuring out specifically what he has, and more time figuring out what category of hand he likely has based on his actions up to that point. Some boards and actions will give away some very specific information, but a lot of times all that need concern you is that he has a general type of hand (like one pair or a weak draw) that is consistent with his actions (weak bet then call a raise on the flop; check-call the turn; check the river). It's possible that this is some crazy slowplay, but worry about that when he raises you. Generally his actions translate to weakness, and your hand has great strength - so make a bet he can call if he has what the large part of his range consists of. Which to me is a pair of queens any kicker, maybe A9 or K9.