I haven't ever hatched eggs, but I did read on here, that you can use a bit of normal saline to wash the eye off. Something about some of the goo dries on the eye from the egg, and it needs to be washed off.
Anyway, I know normal saline won't hurt anything as it's what people with contacts use! If that didn't work, I'd try putting a bit of eye ointment on it. I don't think I'd try to pry the eye open though. I know in pups that can lead to damaged eyes.