We've resident Germans around here? Didn't know that.
But I can answer your question nonetheless. It fully depends on the publisher. German publishers like dtp actually hire a lot pros, and all their games have convincing, if not superb voice acting. The German branches from EA, Activision and THQ ususally make some good efforts there too, if it is a AAA title. Warhammer 40K games used to be in German as excellent as their English counterparts. Microsoft is inconstant, from great (Jade Empire, actually better than the original to "could be better" for ME to downright miserable like HALO 3). ATARI games in German have always been utmost horrible (Fahrenheit).
Can't say who did the translation for the English Drakensang though. Either it was outsourced, or dtp just couldn't find/afford the right talent. But then again who would give a crap about a DSA game outside Germany anyways? The only good things from there come from Crytek and Piranha Bytes.