Welcome to my 100% Achievement Guide for Ghost Files (MOAC)!
(Note, When there is no commentary in the video, i had to mute for copyright reasons)
Story related and unmissable.
At the end of chapter 5, the real killer will push you into a coffin and that acts as a Hidden Object Puzzle.
We then have to find the same symbols that appear in the coffin to escape.
Go to 1:56:05 to see how and where to do this.
Hope This Helps!