It's probably an iStealer or some shit that will just end up taking any passwords you have saved. What this guy did was probably pause the video after hitting the "NO VAC" button and login to an account that isn't VAC banned. As you can tell from the drop down menu, he has 2 accounts (one which is probably banned and one that isn't). Then he just unpaused the video, and went to settings on his account that isn't VAC banned. He has the usernames censored out probably so you don't see that he was using 2 different accounts.
VAC is a totally automated system in which no one controls. It detects any modified core .dll files and then within a week bans you. If it were controlled by a group of people, people would contact VALVe/Steam support, give their bullshit stories and get unbanned.