Changes

I have thought of three four possibilities: one, he is lying about himself being a former 105th Airborne Crusader; two, a second 105th Airborne Crusaders team was assembled and he was a member of that one (I don't know about this possibility since there has been no mention of a refomation of the 105th); three, since the location is unknown and chipping seems to be a "normal" thing in the world of Year Zero, maybe he was taken and was brainwashed somehow to attack during the ballgame; or four, he quit the 105th before they were all killed in a nuclear attack and decided to become part of the resistance.