The idea that Jack Ruby shot Oswald because the Mafia ordered him to, "or else," is really, really stupid. In this case, shooting Oswald was tantamount to shooting himself; committing suicide.
So, if the Mafia ordered you to kill yourself "or else," what could the "or else" possibly be to cause you to do it? That they would hurt or kill some member of your family unless you do? Yeah, but they could still do that, and if you're dead, how can you possibly stop them?
No, if you actually did it, killed yourself, because of some threat they made, you would not only be an idiot, you would be what we call a fucking idiot, which is the worst kind of idiot. It's the dumbest kind.
And, the people who believe that story, that Ruby shot Oswald because the Mafia ordered him to, are in the same category. That little ditty is really just an excuse to believe in the official story of Oswald assassination. But, why believe in the official story of the Oswald assassination at all? I mean: if you are going to reject the official story of the Kennedy assassination but accept the official story of the Oswald assassination, then you might as well make the killers breakfast in bed, after giving them a good rogering. That is what you are doing if you accept the official story of the Oswald assassination, in any way, shape, or form.
So, my advice to you is to spit in their eyes (rhetorically speaking) about BOTH stories. They are BOTH lies. Both Lee Harvey Oswald and Jack Ruby were just innocent patsies, nothing more. Their supposed roles in the respective killings of JFK and Oswald are just fabrications and that is all. The killers, and the whole Establishment really, meaning both the State and the Deep State, needed Oswald dead. They needed him dead yesterday, or in this case, two days before he actually died. So, they, being the ones needing him dead, are the ones who killed him. And Ruby was just their fall guy. It's 2017. It's time to wake up to this.