Is it safe to get an epidural for giving birth if I have spondylolisthesis?

Yes. It is usually safe to have an epidural with a spondylolisthesis. The best way to be safe is to have a spine specialist review your films and give recommendations to the obstetrician and anesthesiolgist before you end up in the labor room.
Yes. Usually the epidural is given at spinal level much higher than where the slip resides. Should not be any different for the anesthesiologist than normal.
Yes. Just let them know th level of the spondy and they can put it at the one of the other 4 levels in your low back. They work around it.