Hmm well I don't know if he drinks cuz every time I spray he hisses at me profusely. I don't even aim at him lol I also offered drops of water. Maybe ill sit by the cage but far enough he can tell I won't bother him to make sure he drinks. My Ambilobe is simple, he drinks from the squirt bottle.
The only one of our chams that likes to eat leaves is our veiled. A good idea may be to offer him some safe greens. Collard could be a good one to start with, do some research about others you could try. Collard greens should be used sparingly so if he eats a bunch make sure to switch it up!