Neat video. If you block those 2 holes and put holes on the other side I see how the right ear will get less noise. But the gas still has to go somewhere. Being crammed into the smooth bore of the upper, it can go down, or back. Back isn't going to taste good at all. I'm in visioning gas puffs coming out where the receivers mate, out the trigger hole and bottom of the magazine(worse than normal). Still, its worth a try. I've seen carriers on Ebay for like $50 if you need a guinea. It will definitely make for dirtier gun guts.
Another idea. What if you took a couple of these and cut the mass of the filter off flush with the actual fitting, making it shorter. I have used these many times through the years on fixtures and they work great for short blasts of air. Even when the bronze filter gets broken off and all that's left is whats inside the fitting. Which in our case is better anyhow. You don't need to constrict the gas flow, just shut it up.
http://www.mcmaster.com/#air-silencers/=vd0y33 go to mufflers, then sure seal mini mufflers