Alan Wake's Story Was An Altered World Event
The Federal Bureau of Control specializes in investigating, containing, and covering up the existence of Altered World Events, or AWEs. These are basically moments when other dimensions creep into our own, with varying supernatural results. The Bright Falls AWE document found in Control show that the Bureau responded to the events of Alan Wake, but arrived after the events of the game. During Alan Wake, Sheriff Sarah Breaker tells Wake's literary agent, Barry Wheeler, to make some calls and give the code phrase "Night Springs." Apparently, that was Sarah's way of notifying people close to the Bureau of what was happening ̵
According to the FBC, Cauldron Lake, where the Dark Place resides in Alan Wake and the place from which Alan's power to rewrite reality comes from is a Threshold. These are locations where dimensions bled together, and we see a few in Control.
The documents say the FBC has investigated Cauldron Lake more than once in the 1970s, and the years mentioned seem to line up with other events. In Alan Wake, poet Thomas Zane discovered the Dark Presence, the game's antagonist, in the 1970s, and wrote the story that would lay the groundwork for Alan's arrival in Bright Falls. More on Zane later.