Do teams not use the same 11 players on field goal blocks for every play?
I can understand how you get 12 players on defense because someone was confused about what package you’re running, but if you’re the 12th guy on special teams shouldn’t you stop and think “Hey, I’m not usually out here for these plays, maybe I’m an extra?”
Half of the defense stayed on the field. There wasn’t going to be enough time to do a proper switch. That said, it’s on the coaches to prepare their team. When they wasted their two timeouts, they could have known it was going to be a fast switch.