A couple of days can make a HUGE difference! In the last week those puppies are developing a LOT! If it was me I would really ask if they can do it on Christmas Eve. You might have to help, but that is wonderful! I will be in there the whole time for my girl. The vet just needs a couple people to help him out. Ours usually will do one person for each pup (I get a pup started too) and one to help him with what he needs until she is all sewed up.
Let us know how it goes!!