This would be a great surprise.  Brett Partridge was Red John and Tiger Tiger killed him.  That would solve the problem that Red John is on the list, but he will not be revealed in Sunday's episode, leaving one more episode to determine that he was Red John.  Secondly, the Roslind Harker problem can be solved the same way as Timothy Carter.  Perhaps Roy Tagliaferro, Timothy Carter, etc are minions of Red John and Harker's description becomes irrelevant.