Aquarium salt isn't used to draw out moisture. It's used to stimulate the production of slime coat and to neutralize bacteria and parasites (Aquarium Care of Goldfish, David Boruchowitz; Aquarium Care of Bettas, David Boruchowitz). Epsom salt (magnesium sulfate) is used to draw out excess fluids in bloated fish as well as to stimulate their digestive system.
Ich looks like little particles of salt scattered across the fish. They are slightly raised but only a little.
A clearer, close up picture would be required to properly diagnose ich but judging from the pictures, he has at the very most an extremely mild case. Ich is present at all times in our tanks and on our fish; it's only when fish become stressed and their immune system is compromised that the ich can take over.
Furthermore, a high heat treatment alone doesn't kill ich. Raising the heat speeds up the life cycle of the ich parasite but it doesn't kill it alone. The high heat treatment for ich is only effective when used in combination with 3 tsps of aquarium salt per gallon and daily water changes.
Again, I suggest you place him in 1 tsp of aquarium salt per gallon in a small hospital tank. There is no need to medicate or to treat for ich. Doing so will only stress the fish.