PAM doesn't work well with aspen or cypress - too many places for the mites to hide. If it's clean and you want to salvage it to use after the mites are gone, put it into a roasting pan and bake it in an oven at 200*F for half an hour to kill any mites and eggs hiding in it.
In the meantime treat the enclosure and paper towels or newspaper you will be using for substrate with PAM. Once everything has dried you can return your snake to the enclosure.
I also use Reptile Spray on the snake.