I think he had it right the first time - that's KCI.
AR 6-3-1-III. Beyond the neutral zone A1 is standing or running between a kick
in flight and B1, and (a) A1 is struck by the ball while B1 is in a
position to catch the ball; or (b) B1, in attempting to catch the ball,
bumps into A1. RULING: Illegal interference. Penalty—(a) and (b):
15 yards for interference with the opportunity to catch the kick.
AR 6-3-1-V. A Team A player beyond the neutral zone first touches or catches a
scrimmage kick that no receiver could have caught while it was in
flight. RULING: Illegal touching but not interference.
Sure looks like A1 ran between the kick in flight and B1 while B1 was in a position to make the catch. I'm not saying he was going to make the catch, but he was in position to do so. In fact, his reason for pulling up may well have been the proximity of A1 to where the kick was coming down. B1 had hs hands out, A1 got to within a yard of him and had the ball hit him. WHY would the crew wave this off?