I posted two photos (different forum - sorry) of the Combo 101 I saw when I visited Safari Condo in Quebec.
Two photos of the Combo 101Photo #2 shows the hitch attachment.
It was an expensive item at $1,700 or $1,800 but it looks very well built. I haven't seen any other options for two assembled bikes and cargo. It includes the rack with wheels. I probably would have bought it but for the price. We were tempted though.
This link:
http://tinyurl.com/8lazpap is the Nicova website translated by Google.
Safari Condo - 1-866-836-6664 - builds Sprinter based Class B Vans so maybe they'd be able to answer your questions if the folks at Nicova can't.