Cool deal! What was Promo 1? The bonus cards?
Huh! I don't know, and also I can't find any info about it. I doubt it's the bonus cards, since the new Krampus haunt is labeled "Promo Haunt 2" and numbered "Haunt P2," implying there should be a "Haunt P1."
My guess is they've prepared two (or more) promo haunts but the schedule for releasing them slipped and they went with this one first due to the holiday theming. If I'm right, we should see a P1 released sometime in the new year!
I've sent Avalon Hill/WotC an inquiry via Facebook, and I'll post here if they respond.