Incidentally, Pyxis asserts (and my own experience concurs) that most wrong-enders manage just fine on their own. Good luck with your hatch!
EDT: Also, I missed it the first time I read the linked article, but because wrong-enders miss the airhole, they should be allowed an extra twelve hours to hatch because they pipped internally and externally simultaneously, and are therefore ahead of their siblings. But they still need the same amount of time to absorb the yolk/blood.