Interesting disease thanks for sharing!

Sounds like a spore forming bacteria similar to c.diff but with servere neurological effects. One thing to note about these spore type bacteria is that they are hard to get rid of and can survive in previously contaminated areas. Once a host is infected the mode of transmission is through fecal mater containing the spores.

In a hospital setting we bleach everything that could possibly become contaminated and isolate patients. Bleach is the only thing that can effectively kill the spores unfortunately since we are talking about dogs we have to look at his living area, if which is a chain spot, may be contaminated by spores living in the soil.

I would isolate the dog if possible in a kennel setting with concrete bottom and clean up stools ASAP, and bleach the area like no other to avoid transmission to your other dogs. If you are thinking it was caused by a raw diet the initial infection may have been, but reinfection could very well have come from previously contaminated areas on your yard.