Meal worms, crickets, locusts.
Try anything, cat food is ok in small doses, just like pinkys and can o snail.
I would buy a bulk of Giant african land snails - try ebay or somone who has extra.
Mine loves them.
Put the meal worms in a veg/fruit mix and the movement should stimualte him to eat fresh.
Or squash a snail up in the veg, not nice but he'll eat it
GOOD LUCK, PICS?