@mattsinger
if your 3/4 zipped eggs have living chicks in them and its been 24 hrs i would help them, usually by day 23 i am done hatching.. there either dis or hatched..
for the dried membrane over eye, either way, wait and see if it flakes off or use moist paper towel.. or take it to the fawcet with warm water.. and put water on finger and work it off.
i do have a policy, if they dont hatch even with started zipping, and i can see or hear them chirping, i help them out , sometimes they get stuck.. and usually its the last day of hatch. dont help untill the last day,dont want to be opening the bator during lockdown, hope that helps for next time if its to late this time.