are you sure its dead? It takes a tremendous amount of energy to hatch, it might just be taking a break to gain some strength. I would wait until the other one who is breathing is out, and fluffed (up to 24 hours) before you take the other one out. In nature, the mom hen will continue sitting on any unhatched eggs for 1-2 days before she gives them up for dead and takes the live chicks out into the world. So give the last eggs a day or so before you count them out. If you want to (I know this is a no-no but I do it), you can candle the eggs during lockdown and see if there's movement so you'll know if it has died or not.