Here is my theory...

First of all , Sheriff Thomas Mccalister is someone fits descriptions , more than that ,
He seems to be the most clever from the suspects ( You can check out S06E03 ,he analyzes the dead body exactly alike Jane). 
He has the fear of Pidgeons , i think it's clue , almost in each episode on season 6 , we see pidgeons,  Just Thoughts...

Now , we move forward for the Clue...

Moments before the explosion , three suspects was in a side of the house , jane in the middle and the two others in the other side , Haffner , stiles got killed by the bomb , Jane got injured, smith and Bertram had very low injures , but Mccalister why is concidered dead!!!

The Only solution, if he hadn't got shooted by Jane, is he fakes his death. He moves somewhere and when he will know that Jane told medias that Gale bertram is Red John , he will appear and try to meet Jane to show him that He is the real Red john, and that he hates copycats.