I have now cleaned my inbox a bit!
Getting a permit to fly wasn't terribly difficult when I wanted one for me. I don't know anything about the background of the plane and flight, just what I've said here.
I don't think this is something that would be picked up in a preflight. I wiggle the wings of any aircraft I fly to shake any water in the fuel to encourage it to make its was to the sump for draining, but the lack of a bolt, i suspect, would go un-noticed as it sits in a slight recess, so a rocking of the wings wouldn't I think, dislodge it.
Nasty business, that, no matter which way you slice it. Even happier now with my low wing Piper, I think I'll notice pretty early if someone has unglued my wings!