I think you'll find that the industry is a little concerned about placing additional hardware and technology on the Mercedes chassis since it could void the warranty, since it's already a 'complete' vehicle when it arrives at the factory, unlike Ford and Freightliner raw chassis that the factory 'completes' during the build, adding the necessary 'additional' RV type devices and products.
A salesperson at a RV dealership could have some Mercedes chassis' from one brand do something differently than another does, so the confusion is not uncommon.
__________________
|