I think the original post makes too much excuses for the ones with the stronger motives. The Robin thing doesn't hold water at all, he's Dick, not Jason. Wolf was introduced after they suspected there was a mole.
I think Superboy is most likely it. I agree on the reason. Much more knowing that Luthor can control his mind. He can easily go back to normal for the next season.
...Still mad that the only satellite member not nominated for JLA membership was the Elongated Man... doesn't make sense at all.