Might as well, they're no going to be able to pip, they aren't going to be able to position them selves to get out. you don't really have to worry about shrink wrapping, it'll be easier to do what you need to with it open.The whole aircell? It’s an Olive egger so it’s hard to see through.
maybe start at a spot where you know the aircell is. and once it's open you'll be able to see where the shell meets the inner membrane. use a wet qtip to make the inner membrane see through before you start making holes, avoid any veins.
(I've done several assists but never twins, I've never had to start an internal pip, so I'm really mostly guessing for the beginning. but the pointy end of the egg has huge blood veins so don't go messing down there before the aircell inner membrane veins are gone)

It's bad enough wondering if you 'might' have to step in at some point. Even worse when you know at some point it's all on you (sorry, that probably makes you feel even worse - but you can do it)! I'd give them as much time as possible and hopefully they will start to get vocal when they are ready to start the hatching process. Talk to them lots so that they know someone is there waiting for them.
