That's not true, sorry. Humans originated on Coruscant, and the Ratakan Empire took some of them off world to become slaves. A few had already been sent out into space via sleeper ships, but it would take hundreds, or thousands, of years before they reach another planet. Though the Celestials were very capable of extragalactic travel, there is no evidence that they ever did so. Plus, every species to come outside of the Galaxy (the Yuuzhan Vong, Abinmor, etc) all existed outside the force.