If she has mites you'll have to tackle them head on. You haven't actually asked how to get rid of them but here you go anyway
First remove your snake from the room and put her in a clean click-clack or similar and use a flea bomb in the room then use Top of decent spray in the enclosure. Thoroughly clean out the enclosure/ soak everything in hot water (mites will drown), with a bit of permoxin if you want. Bathe her in a VERY diluted permoxin solution for 5 min then rinse her in fresh water (be careful with the permoxin its for dog and horse flee treatment so is very strong, some say not to use it for snakes, but you can use soap/ detergent instead I believe. Permoxin is also deadly to cats just btw). Keep her in qurantine while all the mites drop off. You should repeat this about 13 days later as you have to break the mites' breeding cycle and get any that may have survived.
I received my Bredli with a pretty bad case of mites and this did the job, although I didn't actually repeat the treatment, it seemed the measures I took annihilated them!
I hope your Stimson doesn't actually have mites, but if she does this should help.