He was a veteran, which made it a "damned if you do, damned if you don't"-type PR situation. Let the dude on, and, well... the worst-case scenario occurred. Follow protocol and deny him access, and there's a very high chance that either he or his family will get pissed and go to the press about it, which leads to such wonderful things as "Disabled Veteran Denied Ride On Roller Coaster", which is probably an even worse PR issue and leads to such wonderful things as large-scale boycotts, lawsuits, and a general trail of horrible PR.