From what I can think the only reason Patsy Ramsey would write the ransom letter (it's obviously her writing and has knowledge about John's finances only she or John would have) would be to cover for a family member - herself, her husband or her son. I don't think she'd do that garroting business so it was probably the husband or son. More likely the husband. With non-family DNA there, there might have been one or more people also present, presumably other men. Maybe this was a ritual that backfired. I doubt if they intended to kill her.

Also, if these were outsiders, I don't think they'd spend time doing things to her in the basement. They would have grabbed the kid and taken her somewhere else.

It's not this guy, people confess to crimes all the time, and it's a real insult to the public to try to push this nonsense on us. Nobody with sense buys this.