I completely agree that you come across as a rock solid, legit, known provider and am surprised that a hobbyist with his credentials would bail out on a well-known provider after he made it to the parking lot. Then again, as MB said, different guys have different levels of comfort/paranoia, and we don't know whether he saw something in the parking lot that might have spooked him. Hopefully he will contact you to clear it up. If not, give him hell. Hopefully it will be a LONG time before you experience that for a third time. Again, sorry it happened to you ... and VERY sorry it happened to you in Arkansas.
Would it be wrong of me to hope that the guy lived on the Texas side of the border?