My dog won’t stop regurgitating his food?

My dog ate a weird carcass when I took him camping a few months back. Since then his stomach makes weird churning sounds, sounds like his stomach is trying to digest? Currently, he is unable to hold down any food without it coming up later, as foamy bile with food bits. I’m currently feeding him ground turkey and pumpkin, as per recommendation from my vet due to my dog’s picky nature with food. He is drinking water and still has an appetite.

Since these changes, I’ve brought my dog to the vet 3 separate times and they say to offer him probiotic food. We’ve done blood work, and a x-ray. His blood work comes back normal, however his X-ray shows some inflammation in his intestines.

I don’t know what to do to support my dog’s wellness as he seems visibly uncomfortable as he hides in the dirt when he’s in my backyard. I also walk him twice a day. Any recommendations would be appreciated.