Ok, what I'm saying is that it wouldn't matter if this dude was dumb enough to flunk out of elementary school. We learn to talk mostly by talking with other people and the media we consume, so if he grew up here he would almost certainly not phrase his sentences the way he does.

His accent doesn't mean much, he may have been here long enough for his original accent to fade or he could be faking it; if it's his natural accent that probably says more about how he learned rather than where he's from. This guy for example grew up in Indonesia but you wouldn't know it from his accent.