Left Behind

This butterfly effect will only become available if Chris survives the wendigo chase scene and Ashley didn't leave him to die outside. The second option is the best choice so far but if you opted to leaved Chris, Ashley can still talk to him and he'll rejoin before entering the sewers/mines.

Butterfly Effect: Investigate the noise (Ashley)

While Ashley is catching up, you'll hear Jessica's voice coming from an alternate path. For collectors, choosing to investigate the noise is the best option since there's a totem that can be found there. However, this is also a Death flag for Ashley. Opening the trap door will let the wendigo in and kill Ashley. This will unlock the “You Let the Wrong One In!” trophy. If you want, you can exit the game, back up the game save, load the game and deliberately open the trap door to get the trophy. After that, make sure to copy your backup save and overwrite the save on the console so Ashley doesn't die. The best option is to leave the trapdoor alone and walk past it.

Butterfly Effect: Investigate the noise (Chris)

If Ashley is killed, Chris can also be lured and opening the trapdoor again will also result to his Death.