When a snake has an RI you raise the temps AND the humidity.
It's the first thing the vet told me to do was to make sure the humidity was up high, and the temps at about 95 degrees.
OP, do not wait if you know the snake has it bad, they can go down hill pretty quickly when it's bad.
You'll need to get a culture, make sure the vet isn't doing 20 different tests on you, just request a culture and find out what is effective to treat it.
Good luck! Been there, giving shots is no fun![]()