I find it increasingly difficult to have an idea what to think with session reports here but with this one I'm a bit concerned with the combination of

"the one session that I attended put me off playing for the whole weekend", "I am not a beginner, I have nearly 20 years gigging experience with a wide range of people" and (from what I can gather) the knowledge that there were other sessions.

My own 25+ years of experience might well have told me to forget that one (and I might not have thought much of those involved) but it would not have put me off playing for the whole weekend. If I was a beginner, it might but these days I know enough to keep looking and am confident enough to believe I'm in with a chance of finding something where I might be able to fit in.