Oh that sounds so sad
.... Personally, I begin with washing his pouch make sure there maybe isn't any type smell that disturbs him. I never use any softeners or any item in washer or dryer that would normally make our clothes smell good to us...it may be offensive to them as they are so sensitive to smell.
Also our two gliders like blankie's in there sleep pouches, we cut up several pieces of fleece, oh something like a 4x4 or 5x5 inch square pieces to make the pouch soft and comfortable. They love to tunnel under them.
Another thing our loves that you can do too, it's not meant to be a replacements for sleep pouch, but would be better than his food dish is I have taken a piece of fleece....oh say size of a hand towel, and folded it several times and have put it in the bottom of the cage....our two loves to tunnel between the layers and peek out.
I don't have much except, those things came to my mind. I hope it helps some. Keep me posted.