They were pretty elaborate about it. It was supposedly a member of a gang in mexico that the Arizona Hells Angels don’t encounter much. Also it was set up to be a murder and burial in a shallow grave in the desert (no police) They even put part of a cows stomach on the guy’s head and it looked pretty realistic when they were done.
I think the name of the show was “In search of history - Arizona Hells angels”.
Gee, almost any shmoe who could visit a butcher shop and buy a disposable camera could do that.
As to the “other gang” — they had to know that, until the ruse was exposed, that added the other gang to the HA’s target list. Unless a truce is bargained, it’s like Hatfield and McCoy. If something had happened as a result, I wonder how the pair would have felt ethically about that.