My job at FBM in Spain is to socialize the spooky and traumatized dogs. Take a long leash and make a noose at one end. When the dog in backed into the wall, don't face her. Keep your back to her and slip the noose part over her head. While you're walking her, don't acknowlege her fear. Just keep walking like nothing is wrong. You can talk to her, but don't baby her. She might buck, but just ignore it.
The Spook Harness from Majestic Collars has been a life saver for both Iker and me. Once you get the noose over her head, you can take a leash and attach it to the harness.
Good luck! This tecnique has been very successful with lots of galgos.
Sorry, I posted this without reading your update. Seems like all is great