The Germans and Russians were not voice acted by actual Germans and Russians.I´m not too sure about that. I heard the 222 voice actor in an (English voiced) replay and the way he pronounced "Zweihundertzweiundzwanzig" made him sound pretty German. Usually foreigners won´t be able to pronounce that flawlessly. At least he must have had basic knowledge of German.
They sound very bad.You need to hear the Russians in the German version.
The biggest annoyance in this game though is the (ger version) voice of the Panzerfüsilier. This guy is trying so hard to have a strong or deep voice that it becomes ridiculous. The voice is so fake it makes you cringe.