I'm pretty sure, (if I'm understanding right), I already did that, unless there's a different looking keycard. I've been in all lvls except the last and still can't find it. Might just be bc I'm dumb, but idk. Managed to get all scenes tho XD.
Nvm, I just figured it out. I'm just blind. My bad. Thank you for the help
in my case, the last one for me was in Duncan's room, right next to his "nintendo" console, under the TV.
