@Persephone said..."Maybe I could pry his mouth and stick one in"...please don't do this. In his condition you might break his jaw. Better to drip water very slowly on the end of his nose and when he starts opening and shutting his mouth to drink slip a cricket BETWEEN his teeth so he bites down on it.
Also....what temperature is it in the cage where he keeps falling asleep? You don't want to bake him but you want the temperature to be warm enough for him to digest his food, etc. He can't likely move out of the heat because of his condition so you have to be careful.
Having him out of the cage will make him cool off and not be helpful to his recovery.