How is Admiral Rolland wrong in his assumptions about Torrance-Smythe in the novel, Where Eagles Dare?

Torrance-Smythe is a fourth M.I.6 section head whom Admiral Rolland suspects of being a traitor, but it turns out that he is the only one that Rolland is wrong about. Torrance Smythe is murdered by one of the three traitors behind The Wild Deer Pub.