I think the acid reflux is probably due to the condition of his gut right now. I feed THK base mixes, and my girl will get acid reflux if there is too much fat in her food-she does not tolerate fish oil at all on THK. You may want to try a little Kindly base mix and add your own turkey and see how he does. The base mixes are not ground as fine as the complete mixes, such as Embark, and I hydrate those a lot longer, 4 to 12 hours.
I had was giving my girl probiotics for over a year and mentioned to the vet that I did not think they were helping her, and he suggested adding the kefir. I took her off the pet probiotics when I could not add 3 kibbles to her food without getting diarrhea, and then added kefir and had no problems at all transitioning to another kibble. (She does better with a few kibbles mixed into the THK).
Since the THK is bothering him right now, and he tolerates potatoes and sweet potatoes, you may want to try a little of that with the turkey. White potato has less soluble fiber than sweet potatoes and might be a good choice. I strongly suspect the squash and oatmeal are too much for his system.
Have you tried the Wellness Simple Turkey or Natural Balance Duck and Potato?
With the journey I have been through with my girl, I definitely know what it is like to feel defeated and ready to give up–every time I get a good combination that is working formulas are changed or discontinued. I don’t know that I will have any answers for you but can help get you pointed in the direction to head.
