Im thinking JR' role, might've been to drive/drop CWW off at the crime scene, and
then... hang out at the dog park till CWW called for a pick-up.
There probably wasn't much for CWW to clean up afterwards. Once he got in the house (IMO with a key) he changed into his coveralls, footies, gloves, surgical mask...and waited. Once FINISHED, he striped off all protective ware, stuck it in a carry-all igloo ice chest (one was taken from JR' van during raid) called his partner/driver, and skedaddled out da there.
We know that JR took his phone with him, so if a call came in from CWW around the time of the murder (rather than the other way around) it could appear as if it was CWW who was looking for a pick-up.
The thing that puzzles me though, is why pay someone $10,000 just to pick someone up. I had pictured JR as the killer because of the money and his facebook comments re hammer and also his supposed claims of being a hitman. But I could be wrong, as CWW also has a very sketchy history.