Oh, you are in such a tough spot. I really feel for you.

Each of us can only think of what we might do if faced with the same issue. I think in my case, I would try to reset and go back to the beginning, and just walk a lot.
Dealing with extra weight is so overwhelming---I imagine many of us have put on some weight and that makes us so frustrated. In your case, maybe increased walking, even if it was at your rec center would help with the weight. I know the extra weight just adds to the pain and mobility issues for all of us.
I wish you had some other options in terms of getting a 2nd opinion.
Have you used any topical lotions/sprays on your areas of pain? Or tried CBD oils (either topical or capsules)? Not THC psychotropics, but just the hemp based CBD?
Also,the Daily Om has several online classes that include Chair Yoga, Spinal Reset, and Overcoming Stiffness, that I have used, and liked. I couldn't do everything, but could modify and do a lot at different times. Just a few ideas that are different than what you currently are doing.
Maybe pick one or two new ideas out of the suggestions people have offered you, and try them for a couple weeks to see if anything helps, even a little?