When I got one mf my males, he was in such a state. He had a retained eyecap, and also some retained skin. I made an overly humid setup for him and left him in ot for one night; it consisted of a medium sized rubbermaid with about a centimeter of warm water and a bunch of wet sphagunm moss (unmilled.) I placed the UTH under it to keep things warm (it was on a low setting) and added a small rubbermaid hide for him. Next morning, the eyecap rubbed off using nothing more than my fingertip.
Putting in a damp washcloth or towel might even make it possible for the snake to rub the cap off itself.
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2.1 Ball pythons: Goblin, Nothing, and Bela
1.0 Boa Constrictor Imperator: Apache
0.1 albino Cranwell's horned frog: Bene
1.0 Tiger salamander: Slasher
1.0 black kittycat, Inky
A bunch of Oscar cichlids, one giant pleco, huge breeding lot of "fancy" (read: deformed) goldfish, and me an' the boyfriend.