I can't eat many of your list of foods - probably 2/3 of them, including cinnamon, which seems like a weird one. i also can't eat oregano, basil or mint. i went gluten-free for 8 month - also fanatically so - and saw zero difference. I use Enzymedic Digest every time i eat - you can find it online or i buy it in a local co-op type store. i take probiotics and lactase enzymes. Those help me tremendously.
http://www.vitaminsh...1A&gclsrc=aw.ds (I don't buy from them, but this is the brand. There is a weaker version, Digest Basic and a stronger one, Digest Gold)
http://www.digestive...ormula-32-count (I take 1-2 of these daily and they help with any lactose you encounter - i would take a probiotic if i wanted to eat ice cream, but for things like sauces these work for me.)
There was a study done - can't lay my hands on it now - which said that Align is the probiotic that is most helpful to people with IBS.
I recently went to a gastroenterologist who said if a food bothers me don't eat it. that was very helpful, as you can imagine. It made me furious. My daughter had discovered a naturopathic doctor and was seeing her (in another city) for the same kind of problems. I made an appt with her and have just finished testing for a couple of things. Don't have the results yet.
one is for the MTHFR genetic mutations: http://mthfr.net/ This is apparently a common mutation and it has extensive implications in the body. I read through this and thought it described many of my issues and those of my family members. Look carefully at that site, because if you have the genetic mutation it keeps you from being able to "methylate" folate, which affects everything.
The second testing I did was for SIBO. You mention it above, but i'm unclear if you had a stool test done that looked for it or if you did the breath testing. My understanding (i'm not an expert) is that the breath testing is the appropriate way to test for it. Here is an excellent site with a lot of good information: http://www.siboinfo.com/ If you haven't done the breath test, you might try it.
If you're not using digestive enzymes when you eat, that would be a great first step. I don't think they can hurt and they may help.
I have taken Betaine HCL which increases the amount of acid in your stomach in order to break down food. I prefer the digestive enzymes, but last night i read a site about how we tend to need more acid in our stomachs and not less. I wasn't familiar with the site and don't know how accurate it is, but someone passed it on to me. fwiw: http://balancedbites...d-not-less.html
I don't think the pills i've mentioned above substitute for figuring out a cause if possible, but in the meantime they may get you out of pain and help you process the food you are eating. I have felt like the digestive enzymes have literally kept me alive for the past 15 years. i have had chronic diarrhea after eating for about 40 years. not a good time.
Good luck to you! Your situation sounds dire and i hope you can get some help. If you can't get help from the gastroenterologists, i wouldn't hesitate to try a naturopathic doctor.