33 = Keystone. They're trying to say he's a keystone. Maybe also trying to say he's the stone the builders(Freemasons) rejected.
Psalm 118:22 (21st Century King James) The stone which the builders refused has become the head stone of the corner.
Wait scratch that last part, I think they're just saying he's a keystone of the operation. Thought you were talking about someone else.
One keystone. There's lots of different types of keystone's. Kennedy = 33 = Keystone. But he's a keystone the builders (Freemasons) rejected.