If you're asian/white in a black majority school with a black teacher (representation matters!), you are screwed.

I did something similar and caught flak for being dumb enough to intentionally get a bad grade

I would have done the same. The teacher being WrongTM does not mean I should have to redo all the coursework to get the already earned grade for It. In the described situation I know I would have been able to recruit support from multiple people to get the teacher to behave correctly. Fortunately, no teacher in my life would have been able to defend refusing to give credit for work done within the written academic standards.

Although, I did once transfer into a school whose headmaster refused to accept transcripts from another school. He claimed I couldn't have begun grammar school when I did, because my birthday was after his school's deadline (despite him acknowledging the other school's later deadline!), which to him meant that I 'must' have started a year later and therefore 'must' either go back one form or if we didn't like that, have my entire transcript rejected and repeat all forms. (Madness!)