Good evening @kp6350, I am out of my element here a bit. And yet I noticed that you have flat feet which appear to be a factor in the successfulness or unsuccessfulness of treatments. My life partner has a pronated and flat left foot. He is hobbling around right now in a boot after spraining that ankle when he fell off our little bridge down by the river. His visit with a podiatrist today revealed some realities and offered some suggestions for dealing with the flat pronated foot. Included were new orthotics and a special brace that keeps the pronation straight. Might that be worth looking into for your debilitating situation?

May you be safe, free and protected from inner and outer harm.
Chris