The active ingredient in PAM is permethrin. This is the same active ingredient in the popular human head lice treatment Nix, as well as other head lice treatments. Many breeders use Nix to successfully eradicate mites. I'm sure if you do a google search you can find some protocols. Keep in mind, permethrin is a neurotoxic pesticide, not a benign substance.

My feeling on wood mites is that they are annoying but not harmful. If they get to high numbers, I imagine they can be irritating to the snakes. You can probably get rid of them by changing to newspaper and spraying down the plywood rack with a permethrin product.