I have a theory that the murderer is still unknown and maybe not even shown in the first episode heres why:
If you look at the residence screen thing you will se a number of rooms named as private then there are those who are named, people who have something to do with the plot. There's Bluebeard, King Cole, Bigby, mr and mrs beast etc but then there's an name that does not appear in the game nor the comic it's J.Homer i suspect that this is either the boy who cried wolf or an new character because in the comic they say that the boy who cried wolf lives on the second floor in the woodlands apt but he's not on the second floor on the residence screen.
The only ones who lived there was Grimble, Flycatcher and Bigby so why would the red headed man be on the second floor? And i dont think the man is Flycatcher.
So i think the murderer is the man named J.Homer and is yet to be revealed maybe he's the redheaded man, only time will tell