Soaking like that does not sound like a good idea to me.
And if she IS getting an RI, you run the risk of her getting water into her nose or throat and making things much worse.

I am currently treating a girl for RI, and while bumping the heat a little and the humidity slightly has helped, I am positive since she already has trouble breathing that soaking her would do more harm than good, especially if she got water in her nose or lung. Not to mention the added stress.

I've never heard of soaking for an RI in my time here, not once. I would hesitate before I followed that advice. Of course, that's just me, but I want more than one opinion when it comes to something that serious.

I am however successfully treating her with antibiotic injections. Even though I knew she was developing an RI, I waited until she presented with symptoms of bubbling and mucous before I took her to the vet to avoid the possibility of a misdiagnoses. But, I put her in quarantine and raised her temps and humidity as soon as I suspected what was going on. I am convinced that I slowed the progression, but once she showed visible symptoms she went straight to the vet.

I wish you the best with your snake, and I hope it's nothing serious.

Gale