Very interesting, thank you. I think that the person with one bullet shot to the head was the person that the killers had the LEAST amount of anger towards. However, the money strewn about says otherwise. Unless that was just a last minute attempt at diversion.
I kind of see it going something like this: "Ok, we killed all the core Rhodens. Gotta go take care of Uncle Kenny too though because he saw us, and can identify us." So they drive 8 miles, hand the dog (who knows them) a treat, walk in and get rid of their last problem. Real quick and clean. Then they throw a bunch of money around to make it look like some kind of drug hit. "Yah, that'll throw off that new Sheriff!"
JMO. IMO. MOO.