Definately sounds like RI. Get the temps in the low 90's and get him to the vet. Bubbles in the mouth means he's got alot of congestion. The vet should run a culture on the mucous/fluid, find what bacteria has caused the infection and prescibe the correct antibiotic for that specific infection. They can drown and die from the congestion. You need to keep his tub, hides and water bowls quarrantined and isolated, away from any other snakes.