How many different assumptions !
I feel sure, all things are
much easier.
For example, at that time German POWs were involved in works in building of different buildings, channels, roads, plants and houses only. In many our towns (including my town) and cities are the buildings until today, which were built by Germans.
Highly skilled German experts (for example, rocket designers, etc) were involved by Russians only after War ended.
As to body doors of these Dodges - here are my versions:
And Petrol tank refuelling hole is in same position as on image in my post, and spare wheel on rear. And canvas top is the same.
The vehicle on this image was developed experimentally by ZiS Truck factory in 1943. And it is obviously, Russian designers had some captured German vehicles before their eyes . Even canvas top looks like German style.
Probably, after tests this vehicle (these vehicles) were not adopted by army, and was remained in a reserve. Later this vehicle has been transferred for L. Svoboda use (and not usual open-cab Dodge, because he was not ordinary soldier, but high Commander Officer of friendly Czech Forces).
What are Your opinions ?