That doesn't sound abnormal. You can increase the humidity a bit for him. If he will tolerate it, you can also hand mist him with warm water. Some chams love the mistings, and some chams hate it, but it does help them with their shed and cleans their eyes as well.
If he tolerates it wet your hands and arms and let him walk around. I create tunnels with my hands and Camo goes through them, usually taking off some shed in the process. I agree with more mistings too. I usually double his time or turn it on for longer when I know he's going to shed. Usually takes him 6-8 hours now.
i have a "scratchy" vine that my boy likes to scratch against to get loose shed of him. I also mist him a little extra along with a series of vines that he can climb though that will grab his loose shed if he so choose to venture through.