Right, I think the bet will stay in 'Pending' form until it is decided whether the game will continue or not and if it doesn't the bet will be rejected.
Well from my experience they decide really fast. They will never hold it on pending for a long time and would rather just refund it for the time being. However sometimes I even feel like if the retiring player is the one I bet on , then it gets accepted even if he retired before my bet even reached.