I would take her to the vet. I had the same think happen last year with a super mojave female. She laid 5 eggs and retained on like your snake way up high.
By forcing the egg down you could cause more damage. If the (not sure this is the right term) ovaduct id twisted then you could cause more damage than good.
The egg needs to be aspirated. Once the pressure is relieved then the duct could open up and let the egg move down. I watched my vet aspirate the egg in my snake. Not difficult to do but it was very intimidating to watch. Don't know if I could do it myself. He also gave a shot of pitocin(or something like that) to help move the egg down.
I ended up having to take her back in for a second aspiration. Also more pitocin.
She finally moved the egg down but unfortunately died before passing it.
I would get her to the vet.
I hope she passes this for you. Good Luck.
Marshall