Welcome @kipwiley, I've had two occurrences/flare ups of PMR but never experienced what you have for PMR symptoms. My own personal thoughts are there may be something else going on besides the PMR but then I'm not a medical professional. There is another discussion you might find helpful if you want to go the massage route to see if it helps:
-- Myofascial Release Therapy (MFR) for treating compression and pain:
https://connect.mayoclinic.org/discussion/myofascial-release-therapy-mfr-for-treating-compression-and-pain/.
You mentioned being diagnosed with PMR after 4 months of going nowhere and pain. Another thought I had about the pain levels and symptoms is that you might be trying to taper down too fast. My rheumatologist always told me to listen to my body when tapering down. He had me keep a daily pain and dosage log to track my level of pain and the dose. If my pain level was above a 2, I either stayed on the dose another few days or increase it by half of the previous taper so that I wasn't going back to the previous amount to see if it helped. Do you mind sharing how long ago you were started on prednisone and your starting dose?

Discovery was sometime mid December through a shot-in-the - dark prednisone z pack that wiped out the pain after 2 days. After that I found a Rheumatologist and we went to 15/day experimentally; mostly successful. Maybe I am pharmaceutical centric but I don't like pills and tapered to 10 with Dr permission. 10mg seems like an acceptable minimum dose. Trying to minimize the negatives. I take a few well researched supplements that definitely make a difference overall but the hands seem to be resistant. I prefer to balance the pain to dosage and look for other paths.