rare things do happen. my point is not that it didn't happen, but that here you have ton of ai slop presenting multiple different fake images of supposedly same story.
among other things, it does not seem to be the case that the kids were one white, one black - the woman decided to do the dna testing when they were 8 months (if they were black and white, it would probably became suspicious sooner). she fucked them both on same day, but it probably wasn't random one night stand from the bar, because she was able to reach both of them for the test.

this is as close to original source as i have found, interviews her attending physician: https://g1.globo.com/go/goias/noticia/2022/09/07/gemeos-de-pais-diferentes-medico-explica-a-superfecundacao-heteroparental.ghtml

translation: firefox built-in translating tool

The woman bonded with two men on the same day and became pregnant with both. Doctor Túlio Franco explained that fertilizations in different eggs happened in a matter of a few hours between one and the other.
(...)
The mother of the boys explained that the children are very similar, but that doubts arose regarding the fatherhoods. When they were eight months old, she did the DNA scans with the man she thought was the father. The result was positive only for one child.

She then remade the exams, which confirmed the paternity for a child. “I remembered that I had been related to another man and I called him to take the test, which was positive,” says the mother.
(...)
According to her mother, the father of one of them took over the two boys and made the records in the registry office. "He takes care of both, helps me a lot to create and gives all the necessary support they need," he said.