This was just posted on the Lucha Underground twitter account:
I have not watched this week's episode yet but I assume it's a video package to hype his debut in the arena next week. Here are more clips posted from the show..oh, and Dish Network customers should check their guide because El Rey Network is now available on Dish.
UPDATE: I just watched the episode. Alberto appears right after the end credits in Dario Cueto's office.