Originally Posted by ZONA
You got the rule interpretation correct. It's just that the ref blew it and did not call PI. You're not simply allowed to just push a defender out of the endzone. I know they can bump within 5 yards of LOS and if they are close to the sideline that's fine, but I'm pretty sure you as a defender can't just push a player out of the endzone while he is running a route. That was a very badly blown no call IMO.
Except that incidental contact doesn't exist once the QB breaks the pocket. Hence why the call was right.