That chicken looks pretty healthy to me.
Alright, for better or for worse, here is what I did. I very gently cracked and removed little pieces of the shell all around connecting the holes that were already there. I carefully did not mess with the membrane much as it wasn't really as dry as I thought it was. I actually ended up with some yellowish liquid on my hand after handling the egg.
The chick peeped and moved while I was holding it.
After putting it back in the incubator, I saw the whole loose end of the egg move as if the chick were pushing against it.
I guess I'll just see what happens now.
I'll keep you all posted.