They aren't under any obligation to pay anything unless THEY previously agreed to it with YOU.
Best bet is to take him to civil court and sue him. If he has the money, good for him, if he doesn't, then they put a judgement on him and when/if he decides to get clean or wants to buy something, he won't be able to do anything until the judgement is paid off. (kinda like the state files tax liens).
Check into your state laws to see what they are....its normally really cheap to file in a civil court.