No, I'm not in any of those videos. Those videos are just example of how well an expert at this game can play. Among the Smash community, I am simply known as EPsilon or UsurperKingZant. You can find videos of me, but even after 1.5 years of playing, I don't consider myself to be anywhere past middle place in skill.
My join date is June 26, 2007, so if you want to go by your logic, I'm still the real Zant in a place that matters. Sure you beat every kid in Super Smash Brothers Brawl, but can you beat an expert in Super Smash Brothers Brawl?