Well opening an air hole won't kill it (in the spot where the air sac is) and you can see whether or not its alive and whether its shrink wrapped or not. At day 23 they SHOULD have their yoke absorbed so you should have to worry about that. If the birds are alive and their membrane is dry, moisten it and look for red blood veins. If you see some… leave it alone! It needs to absorb them. If you do NOT see any, you can chip away pieces of shell. If you come across one later stop, if you rupture it they will bleed. If you damage a bunch badly they'll hemorrhage and die if you don't stop the bleeding. My hen stepped on an egg and caused it to hemorrhage so I opened the shell fast got the bird out and applied pressure to where the veins fed the chick through the umbilical area and stopped the bleeding. The bird is healthy and fine and you can't distinguish it from the others at all. It had a rough start though and I left it in my incubator so it didn't get trampled and could regain strength.
Do you have an incubator? When my hen had issues I moved my eggs into the incubator once i got it up to temp and humidity. I could monitor them better that way.
I know some hatch on day 22 and 23, but if you aren't hearing cheeps and there aren't any holes in the shell you should make one and see. It may be dead or clinging on to life. At this point, I would open the shell above the air pocket if they haven't broken the shell yet.