As a retired nurse I can verify a few of your questions.
1. You must be dilated two at least 2 fingers before they will consider giving your DIL an epidural. For the reasons Amma stated.
2. If your DIL she dilates too rapidly she will not be able to have the epidural because the delivery will come too quickly for it to take effect
3. It will not hurt the baby since the drugs deaded the nerve pain of the mother and it's injected into the facet joints of the spine. It does not go into her blood stream and effect the baby.
I hope this answers your questions and lessens everyones misgivings. If you have any other questions just PM me.
Best wishes to all