No, it was actually one of the bad guys, let me see if I can find it.

Alright, watched part of a video of all the cutscenes, and found that it was the security chief for the Brancos, Theo Becker, who really bothered me. It turns out that he's a native speaker, but just an atrociously bad voice actor, lmao

Some of the Brazilian characters are clearly not native speakers, though, but it's funny now that I remember that what broke the immersion was the dialogue not sounding at all like natural Portuguese, except for the random gangsters you get to shoot.