I am sure it is Virgil Minelli. His original character name was supposed to be RJ patel. He retired at a time when bosco and others died to give Patrick Jane the freedom to investigate. In the recent episode, it is revealed that Miranda (Lorelei's sister) was killed with a fisherman's hook and it is shown that Virgil after retirement was a fisherman. His physical description, power within CBI etc. proves that he is Red John.