The black security guard was innocent. I don't know what kind of person he was individually but he was still a victim of this Nazi scum.
I don't know anything about the black security guard, so I am going to give him the benefit of the doubt and say it was possible that he was working hard to support his family. This may or may not be the case.
As far as the museum. It is a typical holocaust museum run by filthy self-hating Jews, however, if it is under threat from antisemites, we must defend it. Defending it is different from crying to the media about what happened.
I remember Chaim's story about how he defended a conservative synagogue from the threat of beasts that were trying to take money from it in order not to hurt any of the congregants. He didn't care that it was a sick and evil place but did it because antisemitism has to be met with resistance.