didn't do my due diligence in understanding the terms. The CC company will side with NCL.
Had something like that happen when I fought a hotel when they cancelled my reservations after I checked in, and because I had checked in and the hotel only had records of 1 room being refunded, not both rooms, they claimed I used the other room and refused to refund it. CC company sided with the hotel due to their records.

So I am stuck with a sunk cost.