I don't believe in it for the following reasons:
1) Rhoden were not big shots
2) Caliber seems, imo, small for a hit job
3) why kill 8, and not a 9th who would know just as much
4) The choice of location to hit is not ideal: At night, pitbulls, armed victims, neighboring families, isolated route with little escape path.
Most important, the attitude of LE is not consistent with a hit job. They would be looking for associates. The neighbours and acquaintance of Rhoden's would have described visitors and so on. There would be calls to search individuals or vehicles, witnesses.