In my mind there is a high probablilty the "He is mar" clue is a fake. Here is the reasoning:

Renfrew is supposed to have his infos about RJ trough Orville Tanner. In S01E11 Van Pelt alleges that they were cellmate 7 years ago. Now what time is seven years ago?


Jane
and Van Pelt meet for the first time in the pilot so any episode
including Van Pelt must be later than that. We also get a glimpse of Wagners patient calender for Alison
Price. It has entries for 08 so we are at least in that year. Even if we disregard the entry in the calender, there is another exact
point in time. In S01E10 when Jane picks up the call of sophie miller
the date reads 08/28/08.

Since it is Van Pelt reading the info about Tanner and Renfrew we can't be earlier than 2008, therefore the seven year reference can only mean 2001.

S01E23 delivers an other pretty accurate point in time. When Chow and Rigsby question the store owner who sold the elephant they mention Thanksgiving last year and that it lies 5 months in the past. The security tape is stamped 11/27/08, therfore S01E23 happens around April-May 2009.

At the end of the season finale Dumar asks Jane if he knows who Orville Tanner is. Jane replies that Orvilles was an accomplice of Red John who got caught and died in prison 10 years ago. Dumar confirms that.

It is 2009 so Orville died 1999 in prison. It is therefore impossible he could have shared a cell with Renfrew in 2001. It is further impossible in 2001 to share infos about a murder taking place 2003.