Steven Wench is an FBI agent, infiltrate in Visualize to discover Bret Stiles' crimes. In fact, Stiles (and Patrick Jane) discover his status of "mole"; Stiles sent him false clues.
As "Brother Steven", he was one of the teachers in the cult. In this group, maybe, was present Red John's accomplice, Ron Deutsch.
Confront: is Ron Deuscth the bald of Visualize in Brother Wench group (episode 3x03)
Some fans has suspect Wench to be Red John (see Red John Theories).