That is great! Yes, the hole should not be an issue. I personally would not use the Vaseline. They breath through that moist membrane. I am not sure if they can if it is greasy. Regardless, the little bit you have done should not matter. As suggested, keep the humidity up in the incubator. Hopefully, he will hatch in the next 24-48 hours. Most of the time they rest after pipping and finish absorbing the yolk sack for the next day. Then, they zip. Only thing I would watch for is if tomorrow or Thursday he seems to be only making the pip hole larger and not zipping, it could indicate being stuck. You know he has oxygen so wait as long as possible before intervening. You do not want to help a duckling hatch who hasn’t finished absorbing his yolk. Prayers!