Her humidity is really too high- you want 50-60% normally, unless in shed, & even then only about 70%, though I can see why you'd assume it might help. Even mild diarrhea can cause some dehydration, as I'm sure you're aware. And rather than feeding her, you probably should have given her the medication- her digestion might need a rest for best results.
What is the temp. on the "cool side"? A snake pushing to get out might be too warm- at least that's one possibility. Internal discomfort can make a snake restless too, so again, her medication would likely help that.
How long have you had her? How old is she? Did she come from a private party, a breeder or a pet store?
I assume your vet is well-experienced with snakes? What parasites did they treat for? Internal ones, I assume? (they can cause both diarrhea & dehydration)
Your questions are better addressed to your vet- at least he or she has seen her- not much to go on here.