I hate to tell you, you're wrong.
The Refs explanation was what I will point too.
The ref was wrong, that was an incompletion anywhere on the field. We see that kind of play called an incompletion once a week in the NFL, usually on the sidelines, sometimes in the middle of the field, once in a while in the end zone. If the player doesn't maintain control during the fall it is ALWAYS an incompletion every time anywhere on the field no variations ever.
They just replayed the ref's explanation on ESPN, he didn't say anything about the end zone. He said that as the receiver's knee came down (which was kind of garbly and sounded like he might have said something about the end zone) the ball came loose thus no reception and no touchdown.