If you search YouTube for a show called Dirty Jobs, it shows you how they vent sex chicks at a day old. Another show. "How It's Made, Hatchery Chicks" shows the wing method.
Egg Update: There are two (the green and a brown) that I have not seen twitching yet. I finally saw the blue twin egg twitch this morning (thankfully!). I was biting my lip thinking they had already quit. So today is day 20.... Tonight I'm going to go ahead and carefully make some pip holes on the twin egg with a dull pointy object. I'm going to use a flash light to try and find where any veining is, in an attempt to miss nicking any of those if they haven't absorbed all of it yet. Couldn't borrow my mom's camera (she isn't sure where it is right now!), but I still have my Canon point and shoot, and it does record movie clips, so I will be using that.