OK. I checked with an actual “Palero” here at the prison. In layman’s terms, he is a practitioner of religious beliefs that run parallel to Santeria, (which he is very familiar with) but with an emphasis on working with the dead; animals and bones.. It is the Palero’s opinion that this had nothing to do with Santeria. He mentioned that sacrificing cats and dogs are only to do some harm, or cause some bad outcome. Sacrificing a dog is very uncommon. Cats, yes, but not dogs. Also that shotgunning would probably not be the killing method over cutting the animal’s throat. He mentioned that it had tones of “voodoo”, (there could be another New Orleans connection) or, that the guy could have been “crazy”. FWIW, we also had a couple of Native American inmates in on the discussion, and the first thing they mentioned when I read your post out loud was that it sounded more like Native American than any other one thing; the blanket, turkey feathers, holes in a circle on the shell. “Life is a circle” is a big theme with them. I hope this helps. Stay safe.