In season 5 episode 16, Red John kills Lorelei. In episode 22 it is revealed by the CD that Red John knows the 7 suspects in Jane's list even before Lorelei was killed, since Lorelei reads the list. But Bob Kirkland broke into Jane's office only in episode 19 since he does not know Jane's list previously. So Bob is not Red John.
In season 3 final episode, there were 5 people suspected as Red John accomplice including Bertram and O'Laughlin. In the Trap Jane sets, the assassin climbs down to Bertram's room by Fire stairs and is about to climb down to O'Laughlin's room through a rope. Why not directly climb down the fire escape to O'Laughlin's room? Because Bertram was Red John and O'Laughlin was his accomplice, each were given a different room number, he wanted to check both rooms. Also, in Red Queen, Bertram quotes a poem from William Blake. Red John also quotes William Blake's "Tyger Tyger".
For Sure- Bob Kirkland is not Red John
Probably- Bertram is Red John