it's weird. I'm not finding the cards at dustridge, rusty valley, nor whiterain 😕
I didn't either, so I went and did some other random things & restarted the game, and then they were there. I don't know what step fixed it for me.
By the way, the 3 missing cards at night also didn't show up for me until I beat Dodoro, then they were all available. Hope that helps!
