One of the biggest flaws I see on the Offensive side of the ball

Though I see your point, in real time it appears right decision, but two things I noticed.

Penning did eventually establish his anchor, Carr panicked prior to Penning stopping the defenders momentum. He could have stepped up into the pocket. Penning had the defender locked up as far as grip strength
Now having watched this about 10 times, I can only say that Penning is a big, strong dude.

That DE hit him square in the chest and he moved 2 yards and then stoned him. He overpowered him from an out of position stance and off balance. If he could get his mechanics to a higher state he'd be a perennial all pro.