I am looking at a 2020 passenger van with Tow Haul Mode as a selectable drive mode. It doesn't have the Heavy Duty Tow Package or Trailer Brake Controller. The dealership insists they can just add them and that they will be as good as the factory. Another dealership insists that unless it has HD Tow Package on window sticker.... it doesn't have Tow Haul Mode. Thanks.