Use betadine solution for soaking. Mix with warm water until it looks like weak tea. Use a q tip to remove dead mites. Use paper towels or news print. Card board boxes for hides. Throw it away every day and soak the snake in that mix for twenty minutes. Since you already have the Pam use it to spray the cage every day before remaking it and returning the snake to its enclosure. I did that except for the Pam I used a 10% bleach solution for cleaning the cage and was mite free in about 10 days.
Edit:
The pink belly could it be just getting ready to shed? But I'd probably wait until the cage was completely dry after spraying it before pitting him back in and maybe not using the RR