I watched the video repeatedly and there’s no way due to the angle that you can tell that Armstrong didn’t touch Goff. Armstrong was the closest one to Goff. Even the game announcer said Armstrong tripped him up. Parsons missed the sack and Goff got away. The angle of the video makes it impossible to conclusively tell if Parsons ever got a piece of Goff‘s foot as he was falling. If that was ruled a sack it has to be given to Armstrong because he was the closest one to Goff. That play needs to be shown from another angle to get any real clarity on it.