An artificial heat source would be better at this point I think, lack of moisture won't kill the chick but could make it difficult for it to hatch, you can always assist with the hatch if that is the case, lack of heat will kill the chick which is what will happen if the hen kicks it from the nest over night. I would try to get it hatched myself then put the chick under the hen the next night.
If you put the antibiotic cream on the membrane around the pip and lay the egg in a wet paper towel and take care to keep it damp it will likely hatch fine if you keep it warm under a light or similar
If you put the antibiotic cream on the membrane around the pip and lay the egg in a wet paper towel and take care to keep it damp it will likely hatch fine if you keep it warm under a light or similar