I do not recall seeing a dedicated CO podium at the MDR on the K-dam. There should be one for Reservations, along with the one for walk-up. I'll check it out in a few weeks when we board the NS.
The issue we had on the Zuiderdam was that the person at the CO podium was taking folks from the other two lines, even through there was a long line for CO guests. I had heard that there was a huge staff change for our cruise....we boarded the day the World Cruise ended. The entire MDR was chaos like I have never seen.
I believe the NS CO dining room was purpose built as America's Test Kitchen - like the K-dam....hence the diner look.