Different van and, AFAIK, the Multivan is nothing to do with the joint venture with Ford. It's built on VW's MQB architecture
Indeed. The Multivan is the T7, and despite my reservations reports are that it is very decent to drive. The scalable architecture means it can be easily produced on any production line already in use for manufacturing an MBQ vehicle, which is the whole point.
Note it's architecture, and not platform. Key dimensions share the same scaleable relationship in 3D space so door hinges, suspension pick up points, engine mount fixing locations, are all mathematically common, so the robots know where everything goes without retooling.
The actual structure is not shared with any other VW product, as would have happened in the old days of platform sharing where common floorpans, bulkhead and substructure, or modified versions thereof, were often used across radically different vehicles.
The Transit based effort is not a T7, it is simply Transporter, and we should not do it the honour of calling it T7. That may generate acceptance among buyers less well acquainted with its ancestry, which is doubtless something VW would be happy to see without them actually having to be misleading (again) themselves.