Brazil is a very mixed race country, even more so than the US, I think, because there was never a fully segregation period here. Almost everybody has Portuguese, Italian, African, Indigenous and something-in-between roots. So it's kind of difficult for a Brazilian to be completely white or black. Most people are light or dark "pardo" (this is how a mixed-race between a black parent and a white parent is called in Portuguese), which is the idea people normally have of the "Brazilian" race.
So it is possible for a person to go either way, most of the times. In fact, a very interesting political theory here nowadays is called Schrödinger's Pardo. Statistically, pardos can be either white or black, depending on the narrative. The left here uses this a lot. Pardos are black when considering the incarcerated population (thus pushing the narrative that our judicial system is racist and there are more blacks than whites in prisons), but pardos are white when considering people in universities (thus pushing the narrative that there are fewer blacks than whites graduating here).
It comes as no surprise that recently the trend is that the person can self identify as white, black, pardo or whatever. The result is what you saw: people who are obviously not black saying they are just so they can use quota systems (and there are quotas for A LOT of things here). Sometimes it is even very obvious, so some people have been punished because of that, and the "self identification" system has become a nightmare. Some universities and governmental labor selection companies have instated systems to verify the race of those who identified themselves as black. A race tribunal of sorts. Very dignifying, isn't it?
(English is not my first language, so please ignore weird sentences or mistakes/errors)
