User blog comment:Cackling Shadow/How long have they REALLY been here?/@comment-432124-20130114024526

"I mean honestly, how did the Light even know about Rimbor? And how would they have known that was a good planet to send the league to in order to make them galaxy wide wanted criminals? Now that I think about it, how did they know that Starro was a psychic species with a propensity for mind control?"

I doubt that the Reach would have been on Earth for that long without someone spotting them. Remember that the Light was partnered with the Apokoliptans before they were partnered with the Reach. The Apokoliptans could have been how the Light learned all of these things that you're stating here.