I was really impressed by this!
I was constantly on edge and never felt safe or comfortable. The atmosphere (and especially the sound design) was really well done too and it never felt like random assets being thrown together even though it easily could have.
I'm definitely looking forward to the third chapter!
I found the secret by the way but I'm either doing something really wrong or it's bugged for me, since I can't get it to appear (I've waited for quite some time as well and tried several different things) and I couldn't find anything about it online.
P.S.: I've seen a video of an older version of Chapter 1 and it's great to see how passionate you seem to be about this project, since you put so much time into refining it. The version I played was clearly a lot more polished and I think that's really impressive as well.