Sorry, apparently I interpreted "tanks" more literally than you do. The Kübelwagen and its amphibic Schwimmwagen variant were el cheapo jeeps, not tanks; BMW manufactured mainly aeroplane engines. Those "vehicles that they needed to wage war from the Urals to Morocco" mentioned in your third article were in all probability "staff cars", for superior officers, based on (barely modified?) pre-war standard civilian models.

So no tanks, AFAICT. They had enough other companies for that.