I have recently run into this problem. When I asked my TA to have my requested suite on the 6th floor set to a twin bed configuration, she replied back to me with the following: I have spoken with Explora and unfortunately, all suites in the “OT1” category are only equipped with a king size bed. To obtain 2 twin beds, we would have to move up a category to “OT2”.
As you've noted, the only twin rooms on deck 7 (OT2) are adjoining rooms and I was not thrilled about that, so I ended up having to go up another category to deck 8 (OT3).
I also have never run into this when cruising. I would be curious to find out if the king beds actually can be separated or if they are truly a single king boxspring.