I would bet that the french version used the 480i LD master directly, while the german version used a 480p source and digitally up-scaled and enhanced it to 720p, intercutting it with the 1080p general release version that was down-scaled to 720p.
More effort, yielding a vastly superior result...
Which LD version do you have? I have the box set and it is labeled as "Dolby Surround" which is 2 channels (L&R) matrixed out into 5.1, not discrete 5.1.
If you are thinking of the old DVD "enhanced for widescreen" format, which changes the pixel aspect ratio between 10:11 for 4x3 sources and 40:33 for widescreen sources, that standard doesn't exist on BD or 4K discs. Square pixels are the only option on todays media.