Nick, the crazyness is all part of the game! There are no easy answers....Yes, in the wild he would most certainly be dead by now...but he isn't in the wild. Prolonging his suffering...who really knows, you can only do what you think is best. You already saved him, so no need for guilt. If you feel it would help, force feed him, this might not cause him to start eating straight away, but after a few forced feedings he may well start to do it for himself.

If this was my situation I would do this...

Leave him alone for the next five days, no contact at all. Then offer an easy to swallow meal. If he doesn't take it within a few hours I would force feed him. I would then offer food every third or fourth day, forcing if he doesn't take it for himself. After two weeks of this (if he survives the stress) I would re-assess the situation. It's not easy, but hard choices need to be made. Others might have different ideas of where to go from here, but that is what I would do.