What would it feel like for you if your T did show up at the same volunteer event? I'm curious because that's the issue causing the distress, but I wouldn't think it would be a big deal. I've heard if you see a T in public they are trained to ignore you to maintain your confidentiality, so you would have to approach your T for there to be any interaction. I think you should mention it, because it's what's on your mind it's important. That being said I frequently withhold stuff like this that would seem embarrassing to bring up.