I have never seen a vet prescribe the use of a nubulizer on a snake, but a lot of herp keepers do a similar procedure with a mist maker and F10 disinfectant. The diluted f10 is used instead of antibiotics because it kills the RI bacteria. Many snakes have been successfully treated this way. So it's definitely not unheard of.
And I would definitely get a culture done so you're not just searching in the dark blindly trying out different treatments. Baytrill isn't as effective these days as before. A lot of RIs are resistant to it.
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