The umpire observes traveling, stepping out of bounds or another violation by A1. At approximately the same time, A1 tries for a field goal or the referee observes contact by B1 on A1.
The officials must decide definitely which act occurred first. There is no rules coverage to administer the acts as occurring simultaneously. If the violation occurred first, the ball became dead. If the ball was in flight during the try before the touching of the boundary, there was no violation. If the contact occurred after a violation was observed, it is not a foul unless the contact is intentional or flagrant.