Don't open incubator u can shrink wrap them( the membrane will stick to them) add water when all or close to all water gone quickly there is still half they will be okay
Put her in the incubator she can get to cold put the others under a heat lamp I had chickens with those they will dry and fall off PUT HER IN THe BATOR take older chickens out into brooder
If your ducks egg membrane is stuck just bump up the humidity a little bit I had a chicken that had his membrane stuck and it took him 6 hours too break the membrane a ducks take longer sit tight
You could put the littlest duck back in the incubator with them and when that duck chirps and bumps them it encourages the eggs to hatch don't worry if they get bumped by the duck.