Just to inject some history in here:
First of all, there were tons of black soldiers in the Kaiser's army, though most were indeed askari in Africa. That said, there WERE blacks who made it to Germany as citizens and were duly conscripted like any other. I don't know of any who became officers, but I have seen photos of guys who at least made it to high ranking NCO ranks. Also many in cavalry units were used as drummers. That said, they did see combat on the Western front for those who were already in Germany, and were not in any way segregated or disallowed from promotion.
As for WW2, there were no blacks in the SS that I am aware of, however there was a Heer unit raised in North Africa that later served as occupation troops in Crete that did have at least a couple blacks. Also, blacks/mixed race Germans eho lived in Germany pre-war, it really differed from district to district whether thye were sent to concentration camps, disallowed from service, or, in very rare cases, drafted with everyone else. It should be noted as well that most of the so-callled Rhinland Bastards, children of white Germans and lccupying French Senegalese post-WW1 were castrated by the Nazi government.
So basically, yes, in theory, you could play as a black German on the western front and be correct. However I highly, HIGHLY doubt that DICE has seriously gone through that kind of reserach. He is probably either representing someone on the Arabian Front, or a Harlem Hellfighter given that both have been announced as game content.