From what the UF vets told me,
You cannot prove a snake does NOT have IBD, unless they test it's brain.
You can prove a snake HAS IBD by blood tests, or by liver biopsy.
I hope it's not IBD, and there is a large amount of jumping right to IBD, I believe because it's such a very serious issue. Hopefully it's something else.
I'd also wonder why she has gas right there.
Best wishes, and I hope she either gets better, or you get a diagnosis.