I'm sorry you're having such a hard time
. I'm dealing with GERD again these days and suspect I've had gastritis for several years now since my throat has a red bump in the back and my tonsils have been slightly inflamed for a long time. I had an endoscopy several years ago now that confirmed some stomach irritation and the doc put me on PPI's but they didn't work at all so I stopped.
I suggest actually getting tested for stomach acid levels. Someone else may have mentioned this to you but it may be that your acid levels are too low instead of too high. I take HCL/Pepsin capsules when I feel that overwhelming pain in my esophagus and it goes away very quickly. It's counter intuitive to supplement with acid but it really does work. At least for me. Also, I've done some research on Zinc-Carnosine which can heal the stomach and kill H. Pylori which could possibly be a factor with your GERD. I'm just starting Zinc-Cornosine (it's only been a couple of weeks) so I can't say yet if it's working for me. I also take DGL which helps the mucus layer of your stomach as well as protect it.
Maybe some of this would help you! You're supposed to take Zinc-Carnosine for 8 weeks so I can check back then and let you know if there was an improvement.