Looking to solve extreme Post-COVID SIBO gas after 5 years of treatment

In 2021, when I was 21, I got COVID. COVID lasted for around a week for me and was mainly gastrointestinal. Shortly after I "got better" from COVID, I started becoming extremely bloated. I was experiencing extreme stomach pain and gas (I mean so, SO much gas) that was only alleviated for a short time by eating. The gas was so bad that my lower chest was almost constantly in pain and I felt like I couldn't breathe at times. I started my journey with doctors, which I've been on ever since. Here's the rub: I should preface this with my existing conditions: I am athletic, generally healthy, I have chronic migraines from a condition called "Chiari Malformation" that is treated with daily Atogepant, I have a sunken chest (not enough to warrant a corrective surgery, but more significant than not), and a history of being a fairly picky eater. My diet is mostly just carbs, meats, and sometimes fruits. I tested negative for H. Pylori I had an endoscopy performed, which came back clear. I tested negative for Crohns and Ulcerative Collitus. I tested negative for a lactose intolerance. I tried Omeprazole to no noticeable change. Eventually I had a breathe test performed, where I showed reaction to both versions of SIBO. I was officially diagnosed with SIBO. I've done multiple runs of Xifaxan, to no noticeable difference. I had done an initial single round, then three rounds in rapid succession approximately a year later, than another single round about a year after that. All saw no noticeable difference. Each round was about a week long. I had a coincidental infection that was treated with Amoxicillin, sometime near when I had a run of Xifaxan, which I saw significant symptom treatment. Every one of my symptoms, mostly gas, bloating, and pain, were reduced essentially permanently. I have not been able to recreate this effect. I've adjusted my diet the best I can, to minor symptom treatment. I also cut out soda and most fun drinks, so I'm water only for now. I take a daily supplement two times a day called Iberogast, it significantly reduces my daily pain, with not much effect on my gas. I take 20 drops at a time, which I believe is 1 mL. I've started a probiotic called "Align" and have seen significant symptom treatment from that. I workout regularly, which moves gas through my system and helps alleviate symptoms. I've noticed that my gas has caused anxiety, and that when I have been stressed more than usual my symptoms get worse, which usually has a self-fullfilling effect. I've noticed that certain foods will cause my gas and reflux to get bad within an hour or so, but I have seen great effectiveness of Pepcid to treat this specific symptom flare up, usually quickly. - Example foods: foods high in oil (particularly oily fries, pizza, or meats.), certain candies (typically too much, but certain smooth candies such as filled straws.), fatty meats, acidic fruit juices (such as orange or pineapple juice), and sometimes ice cream.

My symptoms today, August 2026, are the best they have ever been, but life is still miserable at times. My gas can get so bad that it hurts to stand. It is mostly upper GI tract gas, which often leads to me feeling like my airway is restricted, it puts pressure on my heart, and causes significant acid reflux symptoms. My bowel movements occur between every 1 day and every 3 days or so, and are usually fairly normal. I do have bouts of Diarrhea and Constipation, but they are not too common. The worse symptom is by far the gas, which I do not think I can correctly put into words the experience.