Other reasons why we can be sure that Brett Partridge faked his death and is also Red John:
1. Remember, outside the elevator, Haffer told Jane that there was "a comeuppance headed your way"? Now why we he tell Jane that unless he KNEW that Brett was still alive and would come back as RJ?
2. The fact that he was the first on the list of 7 to "die" and thus be eliminated. This was what Heller wanted all along to throw us off.
3. Because Bret Styles told Patrick Jane in a previous season, "I know more than you or Red John." Now why would he say this unless Partridge was, in fact, his son, and therefore, naturally, also Red John?
4. In real life the actor who plays BP is about 45 years old.
5. Robin Tunney said she was shocked by RJ's identity. Now why would she say that if RJ isn't Partridge?
6. Remember when arriving at the house in episode 6.2, Bertram told the on scene investigator that he only knew BP "slightly?" Now why would he say that if Partridge wasn't Red John?
7. They never told us whose house it was that BP and Lisbon were found in. Why would BP just go to some random house, unless he went there to fake his own death!
Brett Partidge is Red John people. See how EVERY clue in the show points to him, and only him?