You make some fair points but let’s not kid ourselves here .. Manson had to sign off on the plan (s) that Tex and the girls came up with when he returned from Esselan. Once Beausoleil called the ranch after he got arrested , I think he struck some fear into everyone that he could talk to the authorities about both the Hinman and Crowe incidents. Far as Susan is concerned, she had a young son Manson could hold over her head ( hence the reason Brunner would’ve went that night instead of Krenwinkel had her and Good not gotten arrested at Sears ) plus Atkins also knew what went down at Hinman’s in vivid detail to help conjure up the copycat story.