No. What you're saying there is that whatever YOUR criteria are, however YOU judge a person's race, that's the one holy pronouncement that determines it. More infallible than the Pope, even.
If it's YOUR decreeing that some guy is 100% in the black category, then it doesn't matter if some 100 million actual Bantu blacks think he's a half-breed. If YOU say it's binary, then apparently that settles it, there are no shades. You're THAT important, apparently.
Sorry, that's just flippin' stupid and delusional.
Except AGAIN, for the fact that a mere century ago someone even whiter than Rachel Anne Dolezal could actually be classified as black, if she had any blacks in her ancestry. So again, what you're saying is just that if YOU pronounce her to be 100% in one category, then that's it, that's what settles it definitively, that's all the test we need.
And again, that's just flippin' stupid and delusional.