You can cup feed him, use a deep cup for crickets and most should stay in. You can also raise the floor, if I remember right you have a Reptibreeze, right? That gives him a smaller hunting area but that Corn Plant would have to go temporarily I suppose. You could also go for Phoenix worms. They're small but my cham loves them to death. There's also micro superworms but I've never tried them. General rule is nothing larger than his head/mouth. Soft is good.