Here is the thing. Whether or not you're with the Satanists depends on your upbringing and how well you passed certain tests. Were you brought up with the 25 rules of disinformation?
https://vigilantcitizen.com/latestnews/the-25-rules-of-disinformation/
Did you experience what Johnny Lange did in his household? (video embedded)
Was your grandfather also a member of the Knights of Columbus and perhaps also the Mafia? It is possible he was not, but just was in the wrong place at the wrong time, or that they just wanted to bump him off so someone else could have his place.