The thing is "just so happened" he was nearby at a Western Union carrying a gun goes over to the police station at just at the right time. Walks up to Oswald and shoots him!
Afterwards when interviewed Ruby clams up and never talked about it. He took any secrets to his grave.
Ruby sent a $25 western union gram to an exotic dancer 5 minutes before shooting Oswald. Then walked across the street to the garage. LHO was supposed to be taken out at 10am. All the press were notified, but they decided to question him again. Ruby knew 80% of the cops.
Ruby pleaded to be imprisoned in Washington. Said he couldn’t talk in Tx.