Well they say red john is in the list but do we know there is just one person. Or let me say it in another way, even if there is A red john, there are mor people in that list that serves to Red John. And there is nothing  against that. Bob Kirkland is working for Red John that's for sure. From him Red John learned  what info Patrick has and find out there are only 7 people left. So Bob Kirkland is just  a servant of Red John otherwise there is no mystery there. Also about Brett Partridge, well there are  lots of theories that says it is him but I do believe he is either a missdirection (which is the main concept of this program) or another servant of Red John. I honestly believe Red John is Sheriff McAllister. Why? Well it is impossible to find a clue from a guest appearance from season 1 but the magic word is STAR POWER.
Even fake Red John at the end of season played by Bradley Whitford. Xander Berkeley is the biggest STAR in the list and the most mysterious one.