Can't help you with books or movies, and can't tell you when i'll be finished, but i'm working on the long term Olympic Project Nest Area Recording Project which now has over 1,000 combined vocalization and percussive recordings from around 3 years now, that don't appear to belong to any known animal.
I'm/We're also collecting localized actual visual sightings from that general area of which many aren't via the normal public ways that we gets reports for the SSR, and i truly believe that the general area there will soon enough provide something decent in way of a pic/video hopefully.
Life and bills are right now slowing me down more than i want and that can't be helped, but imo and i appreciate i'm being a little vague here, this project and what it's appearing to yield, is keeping my head in the game, no doubt.