Although glad to see it, I thought the same thing. Although, obviously, the initial ticketing agent didn't have a clue, as she refused to sell a ticket to either team on the flight that was still there sitting at the gate.
My hunch is that somewhere there in the final minutes at SJU, somebody with TAR had a word with somebody from AA to remind them how much pub they were getting/going to get and influence them to bring the jetway back. A threeway race was not essential, but a two-way race certainly was, for good TV.
Someday somebody with status will race and you can just hear them now . . . "But I AM EXP!! You must bring the jetway back!"