Lol he had to get "vortex", whatever that means, and the scalenes in there.
Still, gotta say that's the most reasonable Naudi video I've seen. Naudia saying that myofascial release is not a cure for all and that you need to incorperate motor patterns? Suprising to hear him being right. Also a good point that you need to analyse dynamic movement to spot weaknesses and possibly "faulty" mechanics.
He's basicly using the band as kinesiotape, causing activation/fascillitation of the external rotators while walking, which would not be a bad idea if someone had excessive internal rotation. Still, the problem of knee valgus can be many things, including either the ankle, the knee, the hip or all of the above. Strenghtening the medius (eccentricly), doing other single leg work with the proper range of movement, core work and perhaps ankle stability (depending on the cause) would be something I would do while working on the movement during actual daily or sports activity. It adds up.