The users outside knowledge is the "spectator" aspect of being a spectactor, but still goes through the actor's experience of discovering his brothers death.
We agree with the idea of the player acting as the "spect-actor" in the game "c ya laterrrrr" and believe, like Boal said, that it fosters the player to think more deeply about the experience presented.
We also acknowledge that the user must use critical thinking skills to decipher the death of the brother.