I am not familiar with the details of the upcoming Carolinas Section trip. Perhaps someone else can speak to that.
MBCA still does Germany Trips in the spring and fall. Lucy and I participated in one of the fall trips in 2016 and had a great time. One of the possibilities was to add on a Viking River Cruise after the main event had concluded, with transportation to the dock included in the Germany trip cost. That year it was a Danube cruise from Nürnberg to Budapest, for which 12 couples opted.
The itinerary varies from trip to trip, leading to many repeat participants, but usually includes an assembly plant tour, AMG facilities and a whole day at the Mercedes Benz Museum, as well as tours of places related to Gottfried Daimler and Karl Benz and of interest to car enthusiasts in general. There are always a few people taking European Delivery of a new car in the days before or after the trip event.
One of the tricks I learned from the travel agency handling the Germany trip arrangements is that those opting for the Viking River Cruise could save a considerable amount of money on the airfare by booking it through Viking. The cost of Viking included airfare was considerably less expensive than what the agency could get for Germany Trip event participants not participating in the optional river cruise, and Viking allows one to customize the arrival and departure dates up to 30 days before and after its sailings. The only caveat is that one had to arrive and depart from the same airports that serviced the optional cruise. This meant that those booking through Viking would be responsible for getting themselves from Nürnberg to Stuttgart on their own. Some arrived in Nürnberg on the day the Germany trip commenced and just took a train from Nürnberg to Stuttgart. One couple arrived in Nürnberg, took the train to Stuttgart, took European Delivery of a new vehicle and visited relatives in France before the trip event began. We arranged through Viking to arrive in Nürnberg a week or so before the Germany Trip, rented a car and spent a week sightseeing in and around Nurnberg and Rothenburg, then dropped off the rental car at the train station just a block or two from the Germany Trip hotel in Stuttgart. At the conclusion of the Germany trip event the 12 couples were transported by bus from Stuttgart to Nürnberg.