How come I have never heard of these members in TSM?

I started playing League in last September, and have played the game nonstop, while worshiping TSM; yet, I have no clue who these people are xD (shown in video). How does the hierarchy of teams in the LCS work? Why have I never seen these people in Esports games? What do they do? Thanks for the clarification, and see you in the rift!