convert raw to dng - problems with RawTherapee

On Linux it is not so easy to convert raw files to dng. Currently I do it with Adobe’s dngconverter, which I can use very well via Wine.
But if I want to become independent from Adobe, and if possible from Wine, the conversion works for me only via digiKam.
But there strange problems occur. The dng are indeed wonderfully small compirmiert (lossless), but the colors are then completely different, as with the original and different from the dng of the dngconverter.
And, what is even stranger: The dng from digiKam show a completely wrong lens. Wrongly Olymus, instead of Panasoinc 12-40mm.

grafik

digikam.dng (18.5 MB)

dngconverter.DNG (22.4 MB)

Dießen.RW2 (23.1 MB)

Is this problem known?
And: ART and darktable show the correct lens.