Why is your heat pad only set to 90 while being fed? Where are you measuring the 85/90F? What is your humidity like?
Diagnosing something over the internet is pretty difficult even when we can see pics. He really does need a qualified vet as expensive as it might be. Fungal treatment might be necessary depending what is causing the scales to do that. I feel like getting cut is unlikely in how you are describing things, but again, its really hard to tell without seeing it :/