Viperjet new other jets would be landing and also knew how quick jets go through fuel. He was irresponsible taxing back in the center of the runway. Then to come running up with a lawyer... It was good of Barry to offer to fix the wing but I don't think he had any fault in it. With this guy being sue happy I believe I'd want some kind of a letter as well. I've met Barry and he's a nice guy.
Usually in the pilots meeting they cover taxing back on the side so other pilots can land if they need to, getting out of the way. That and the CDs should be able to vouch for Barry being in the right.
if I was a cd of an event I would be very hesitant of allowing this individual at the event. At the very least make him sign a waiver of some sort.