If it is scale rot keep him on newspaper. Don't use any oil based creams or salves like neosporine or bacitracin. Silver burn cream is what's good for that. The soaks in the betadine are good.
Keep him dry without sacrificing too much ambient humidity. What's the surface temperature of his warm side? It could also be a burn if his underbelly heat is nor controlled by a thermostat. It should be 88/91 give or take a degree. And about 80 ambient temp on the cool side.
As for the dragon.. Bowls are not really required. Many won't drink water from a bowl. They require a warm soak a few times a week to stay properly hydrated. Check out the dragon forum for info on veggies, greens, and insects to feed him.