I wouldn’t go to overboard in hides at the moment, since your snake is a baby and will outgrow them fairly quickly if they’re snug. When mine was a baby, his favorite hide was actually a piece of moss mat rolled into a tube. I’d either wash it or just cut a new piece when it got soiled, and give him a slightly bigger piece as he grew.
Once you’re sure the mites are all gone, you can go back to using hides made of wood, cork bark, fake plants, etc - all that stuff. If you have any concerns about more mites hitching a ride on stuff like that, just buy it online where it will have been sitting in a warehouse nowhere near any other reptiles rather than from a pet store.
It’s nicer for the snake to have a variety of textures and smells and more different places to go. But you do have to keep things really simple and dishwasher-safe until you’re sure the mites are good and gone.