the best advice i can give is really really really hope that he makes this cnx. if not he's going standby on following flights and, yeah, busiest travel day of the year at a station which can have bad weather....so i guess the next advice would be to get the air bnb app installed on his phone

gate and ops agents monitor connection inbound cnx times carefully, if they see anything with less than 30 and they have a large waitlist and they have a no hold mandate and the inbound isn't not coming in at a nearby gate, they'll offload him even before boarding begins and even if he shows up at -11

not a good plan stan, get it changed to something.....luckier