I appreciate Rivera leveling the excitement of Norman to the press, but I bet in his mind he was thrilled to see him making plays and creating turnovers. Even he if was doing some grabbing/pulling, it doesn't change the fact that he caught four interceptions. It would be different if he was batting it down, but he was actually catching the ball.
I may be wrong, but usually when a CB is flagged for pass interference he doesn't get an INT, he just causes an incompletion. Sounds like Norman has the hands of an angel out there.
as long as he is actually playing for the ball, thus turning the intended reciever into a defender, there usually isn't a pass interference penalty.
...but who knows what the deal would be with replacement refs running the show.