And that's the thing. When Dolezal was pretending to be black, she very clearly had two white parents and identified as white at least through high school. It was obviously a lie to claim she was black. But this guy? It looks like he legitimately grew up being told he was biracial by his mother, and potentially facing racist bigotry because of it in his youth. There's nothing to indicate that he "knew" he was white and perpetrated a ruse to gain an advantage not otherwise available. From a strictly subjective standpoint, old pictures of him certainly make him look like a biracial kid to my eyes. So even if it turns out that he is white, I wouldn't be at all shocked to learn that he legitimately believes that he is biracial or has been the victim of bigotry in the past. That's completely different than someone who is knowingly lying about their origins.
That said, seeing as how the primary source of the allegation is Breitbart, yeah, that dude is black. The next time Breitbart prints something true, not only will it be the first time, but they'll immediately print a retraction and then blame their oversight on Muslims.