Welcome to the Peony Forum LisaLisa!
Adrianna from the Southern Peony blog answered a question from a follower concerning lifting peonies if they're too deep. She advised doing something that sounded like a gardening version of mud jacking to me! She told him to put the shovel in as deep as possible on one side of the peony out past the drip line and to lever it up a bit and backfill dirt underneath. I think that would work for fairly small roots, definitely wouldn't get enough movement to get under the big ones. Maybe something to try in the fall. I can tell you from experience NOT to try just removing soil from the top, especially if you're in a damp area as you'll create a divot over the crown that holds water, especially in the early spring as they wake up being waterlogged will kill them faster than anything.
I'll be moving my entire garden from zone 4b to 8a over the next few years; we purchased land to build our retirement home in Calera, Alabama. Always keep an eye out now for people growing peonies in a similar zone so I'll be watching your progress with much interest!
