The truth is no one will have an authoritative response to this. This is a good question, and reveals a gap in the rule that only Shaw and the rules committee can address. They obviously didn't consider the possibility of a player in motion passing through the line between the snapper and the potential kicker at the moment the ball is snapped.
Me, personally, for what that's worth, I would not take away the ability of the offense to snap the ball to a motion back, while, at the same time, forcing Team A to be in compliance with mandatory numbering, and allow Team B to place a player head-up on the snapper. Team A might have an 'option' play depending on the defensive formation, i.e., they may only try for a TD if Team B looks like they are really trying to block the kick. But, if Team B looks like they could cover a TD attempt, Team A might just go through with a FG attempt.
Somehow, this needs to be brought to the attention of the rules committee so they can decide how they want the game to be played.
