If this endo doesn't know that Armour will suppress TSH to nearly 0, there is no hope you'll ever be treated optimally. I'm now 59, and my own TSH has never been higher than .02 for the entire time my MD has been treating me with Armour. It suppresses TSH; no two ways about it.
You have no energy reserve from which to draw because your FT4 is abysmally too low, as is your T3. You simply need more Armour than you're getting.
If you can find a general practitioner, internist, osteopath, or naturopath who is familiar with natural dessicated meds and who practices holistically, you have a much better chance of getting what you need than from almost any endo on the planet. Ask your local pharmacists if they will provide you with the names of some MDs whose natural thyroid scripts they fill. It's worth a shot.
I completely understand the fear of stroke in an "elderly" person. (Have to face facts, here.

From a medical perspective, 60 is considered "elderly".) My own mother began thyroid treatment at around 67 years. (Synthroid, no T3 med.) She began having atrial fibrillation episodes shortly thereafter, and a massive stroke shortly after that. But I attribute it all to the ineptness of her wonky primary MD, who had made several awful treatment mistakes with both her and my dad prior to that. I believe that he either started her on too high (or too low) a dose, or he increased it too fast... Either one of which can cause heart arrhythmias. I'll never know at this point. I was trying to get her to ditch the quack, but she thought of him as a "friend". I-yi-yi.
One thing is sure... You aren't a "hard case". Your endos are just dumbos.