I had mites in my collection at one point, a local breeder recommended I use this product, Natural Chemistry Reptile Spray:
I was able to order it off of reptilebasics.
Sure enough, after spraying some on the snakes and a little in each corner of their tubs, the mites went away. I did the treatment for a few weeks but it did get rid of them.
This stuff isn’t as harsh as PAM and so can be applied to the snake (of course avoiding the head when you spray it!) and you do want to remove any water bowls so they don’t get the stuff into the water bowl and drink it.