Hello @robinray55. I also have TMJ and similar pain symptoms. I also have tried the night guards and wearing them during the day. I have a narrow upper bit and sleep apnea.
Treatments I have also tried: Chiropractic care, acupuncture, acupressure, ice packs, eating soft diet, all still cause pain and my jaws would fatigue very quickly even with talking which would cause locked jaw. Finally found a relief with the removal of my wisdom teeth.

Has the dentist notice your teeth may be crowded?