There is theory about Bob Kirkland's twin to have murdered Lennon and of even being RJ overall.
Come on, Bob Kirkland was the one that killed Lennon, not his twin brother.If you recall, right before he killed him, he asked him "do you know me?", which was the exact same question e asked the people he tortured at 6x05. What was he looking for, assuming he was the twin, himself??And when he did not get what he wanted from Lennox he killed him, just like he did or intented to do at 6x05.
He was sencere to PJ when he said that he was looking for his brother near RJ.And he was killed because he knew about the Tiger-Tigers...