What about #3 , closing the door before T-10? That is a failure on AA if that happened.

I wouldn't be surprised if it did close early with so many passengers not making it they were probably done quickly and after waiting for 5-10 minutes and nobody there I could see them closing the door at T-15. I've made it to flights after a late inbound connection with the doors fully closed at T-15, so they closed at T-20 saying, "oh we didn't think you would make it." The doors should never close before T-10 if there are outstanding passengers.