Revolutionary Todyo
Banned
I think it was discussed on here before, but Nazi policy on blacks was largely one of neglect. Blacks lived under the Reich, and only tended to end up in camps if they were unlucky. There simply wasn't enough of them to pose a threat. It is feasible that blacks in Nazi Britain would similarly be ignored as long as they stay suitably downtrodden. Nazi racial policy was hardly what you would call consistent.
I think they might end up in a similar position to the Slavs, though that depends on how much of Africa is loyal to the Facist government.