indeed, the model and the pictures from Saumur are contradictory, and I could add the Zaloga reconstruction from ther Osprey book (which is incorrect) that would increase the mystery.
The side view is apparently the correct one, but the seat in wquestion is not depicted.
In all photograph sources, the hydraulic seat that that should seat the commander is in the wrong place, on the right side, while the cuppolo, the gun sights and the MG control are on the left side.
My point is that the sources are not reliable, and I need to analyze them:
the written source clearly states the assistance by the radioman, and that the commander serves the gun. In how far the assistance goes, is our point of debate. Since the turret is enlarged (let's not leave out that part) the intention is clear to improve the commander's performance. Now, if I leave out the model and the Zaloga reconstruction, I have the swivel and hydraulic seat from the drawing and from the tank at Saumur. Obviously it is fixed in the wrong place without swivel - so who was sitting on it? Also, another picture of the Saumur tank shows a radio to the left of the driver seat. I also cannot see anything that points to where the second seat is meant to be. If I now assume the drawing to be correct, obviously the Saumur tank is a modification. We know of two deviations from the planned functionality - one is from the french service, where the radioman/loading assistant had no function without radio.
This is the point where the interpretation starts. Maybe the radioman just twiddled his thumbs and occasionally passed some shells, or maybe the seat was removed/replaced/repostioned, so he could really assist. In any case, he would have been able to, since the turret was specifically designed to facilitate that (let us not forget it was used in the B1 too), where the seat arrangement is quite different), in contrast to the purely one-man turrets.
Now comes the german modification, so let's assume the radio on the left is the german one (or the different platoon commander one that the french used?), and let us assume that the efficient germans
thought of fixing a hydraulic chair for the third man. The fix for the swivel is unused in the center (in the Saumur photos).
So I do not have a reliable proof for any assumption, just a written (and subject to interpretation) concept and hints that point to the loading assistance.....