Very nice play by your cousin, though it does highlight some of the stupidity of the defenders. So many people don't realise that your ultimate job is to run the clock down - had the last guy just legged it down the stairs, it would have been an easy win for them, haha. People just want those kills sadly.
I was thinking the same thing. I figured the last guy would've just stayed downstairs and run the clock out, but when he came back up I knew he just wanted the kill. What also cost him is I think he went to melee instead of just switching to sidearm.