This really was a treat! I'm wary of mysteries because I feel like they're usually an excuse for creators to feel smug about how clever they are, but this experience really was catered to the player and I had a fantastic time playing it. Great job!
Glad you enjoyed it! This is a really solid playthrough. I think you're the only person I've seen the diviner call an "ace detective" on their first try. There are a lot of opportunities to mess that up and have him call you incompetent... :)
It definitely did end up way more mystery than horror -- originally it was going to be scarier but I kind of doubled down on the mystery in the end and now it's just a bit unsettling.