The Steelers' final play was a mess. Ben says he wanted to spike it and had called for a spike, but was overruled by Tomlin. However he ran out of time to let everyone know of the change and so there was mass confusion with most of the Steelers thinking it would be a spike.
I heard the Big Ben interview. It was Haley he was saying who said to run the play. They showed a screen grab of the final pass as the ball crossed the line of scrimmage. The only receiver that was even moving was the target. Bell is standing off to the side, two receivers are a step over the line of scrimmage but not in a route, and the tight end is blocking, sort of, but no one was near him. Looks like the players were mostly expecting a spike.
The other thing BB supposedly coaches (according to some former assistants) is to not reach for the pylon / goal line as you are completing a catch. He will bench a player for that. The Pats have gotten a touch back and that incompletion in key situations this year when opponents reach.