Random Encounters?

[gandalf91]

Actually none of them are really random...They're all scripted to occur when a) items are picked up/interacted with, b) you enter certain areas, or c) either a, b or both in some cases but contingent on how low your sanity is.

As per the grunt spawning when you pick up the key in the guest room, it occurs after a short time interval when either performing that action, reading the note, or stepping in front of the closet. If you grab the key quickly enough and dash out of the room you can in fact by-pass the scripted event.