The red one is THE one that needs identification. Looks like a jack plug at first glance, but I am now leaning towards the air line gas coupler mostly due to the brass fitting and anodized section......but still no joy.....yet. I am actually after a shot of the push switch to the bottom.
I never saw the exhibit but it looks like it's not cut out. It looks like there is a piece of black tape over a hole. Where an xlr cable plugged into. you can see in the exhibit photo there is an indentation where there is a round hole.
Yes the port on the bottom is, I believe, a 3 pin XLR panel. Now BM supplies a female, but I can't help feel it is a male which is basically a hole with 3 long pins inside? Would be good to get a conformation of which it is......but having said that they could change from pack to pack as some did not even have any!