As far as the white guy being a security guy, I kind of doubt it. If he is, it doesn't make sense for him to follow her as he did in that last clip. She obviously didn't steal anything, where would she put it? If he was following her to see to her well-being then, as security, he'd make himself known to her, ask her if she needed assistance, etc. IMO
I do see what appears to be the black guy walking with her in that one clip. I don't see any indication that she is bothered by him, though. Hopefully, he will be identified soon. It would be nice to know the sequence of events as far as which one of the two videos happened first.
I absolutely don't understand the white guy following her, though. I really don't. Gosh, for all we know he had seen her with the black guy for some time, followed them and when the black guy parted, continued to follow Hannah. Why would he follow her/them? IDK, there's tons of theories already, so to add to it, maybe he was angry seeing the two of them together because of their racial difference. Maybe he called LE to report the black guy because of the same anger. Maybe he has a race problem. OR maybe the white guy and black guy are friends that actually know each other and are in cahoots. Maybe they BOTH know more than anyone thinks. But really, the only thing that can be said about the black guy is we don't know his name.
FWIW, I think if Hannah were being followed while walking with a short white redheaded man, the questions would be centered around him. What actually bothers me is the thought that if that were the case, I feel like people would immediately wonder if both the man walking with her and the one following her had schemed it, but because they are two different races, that thought doesn't immediately pop into their heads. And it should (at least I think so). I mean obviously it was one, or the other, or neither or both.