EDIT: I have completely misunderstood what I have bought. I thought Season 2 DLC was part of the Super Deluxe edition of Borderlands 3. Not so. Part of the Ultimate Edition, which I could not purchase. So I simply does not own it. How I then could access the diamond key -room I don’t know.
Eventhough I have purchased the Directors Cut as part of the Season 2 pack. I can only access the room at the bay where you get very NICE gear with the diamond key. Could not activate Murder Solving missions in one room, and neither the one in the room with claptrack.