Is there some reason you stopped the Chinese herbs and acupuncture? Fletcher had IBS and we did taper his acupuncture down to about once a month, but didn't stop, and he stayed on his Chinese herbs for his whole life. I would have to ask my vet exactly what he was on, he passed in 2013, so I have forgotten exactly what he took. I also gave him canned pumpkin with every meal, I know it doesn't work for all dogs, but it worked for him. He was also raw fed. Anything processed just didn't agree with him, even if it was a protein source that he could eat just fine if it was raw.
Good luck, dealing with IBS is a life long struggle
Oh, I just saw what you said about the acupuncture, maybe start it again, but not as frequent?