FWIW, after a bit or research - no X30 connectors are located in the door sills of the W221. A variety of X30 connectors are present throughout the interior of the vehicle (e.g., potential distributors for central CAN - X30/20; drivetrain CAN - X30/21; interior CAN - X30/32; interior CAN - X30/33; interior CAN - X30/34) but none of these distributors are located in the door sills.