I would put it in a deli cup on it's own, check on it every other day see if the mold keep growing, if it does wipe it off.
Hopefully it will hatch out for you, I do not remember who on this forum but I remember someone hatching some VERY ugly eggs that most probably would have never thought would have make it.
Alright. I'll do that. I'm going to say a little prayer (and I'm not big on praying) that this little egg makes it. If not, this will be my first lesson in the pitfalls of ball python breeding.