So I just stumpled over this:
In an interview about Season 5 renewal, Bruno Heller has stated that Red John's identity will not be revealed for two seasons, so yes, it is confirmed that the dead man from 4-7 is not Red John.
Does this mean Red John is not dead?
Okay this is just commin' out of no where. But could it be possible that RJ is still alive and kills Van Pelt and Rigsby, because he gets mad for the CBI thinkin' him dead.
Van Pelt and RIgsby are also already meant to leave the show after season 6.
Could this be a possibility?