In GFII an attempt is made on Michael as he nears the window of his bedroom. After escaping unharmed the grounds are lit with flood lights and combed by numerous guards and dogs. Michael meets with Tom Hagen and tells him that if he is right the assassins are already dead. Soon we find the would be killers dead on the property.
So I assume Michael thinks the traitor is still on the property, if not who kills the assassins and is never found?