OP- I've read your post a few times & it's still not clear to me what you're asking- that's why I didn't respond. Scratches on a snake look NOTHING like mites- mites are alive (very tiny!) & moving- they can be black, brown or reddish in color. I would NOT treat for mites unless I found actual snake mites- NOT to be confused with wood mites that sometimes inhabit substrates that people buy. If you find actual mites- you want to treat quickly & thoroughly (follow directions closely so you don't harm your snake), because mites reproduce exponentially & can kill snakes - really!
IF your snake has mites, keep them on white paper towels while under treatment (for over a month to make sure they don't return) & use NO substrate or wood furnishings in which mites can hide or leave eggs. Otherwise you'll be doomed to repeat treatment- & a faster cure is better because chemicals are not so good for your snake, nor is the stress of being treated. (Plastic hides & glass bowls are fine, but hold the "clutter" too.)