That’s because this is upward pickslanting. You can see that his forearm is not supinated as dwps requires. Instead, it’s pronated, i.e. flat against the guitar body. This is the same form used by Andy Wood when he plays electric, and the movements you’re seeing here are very similar.
This includes the occasional 2wps rotation when he needs to move from an upstroke on a lower string to a downstroke on a higher string. The fast EJ-style 2nps lines in the first few seconds of the clip are a good example of this. It’s downstroke and pulloff on the top string, then down-up (rotate) on the lower string to start over.
The faster elbow-appearing stuff is also uwps but not as clean, so I wouldn’t spend too much time trying to pull that apart. The wrist stuff is great and looks good like Andy’s does. For in-depth slow motion look at pretty much the same form, you can check out that interview.
And in general, @aliendough, your main challenge is really unrelated to this. Your mission, should you choose to accept it before the Mission Impossible cassette tape explodes, is to get those uwps elbow and wrist movement happening fluidly with those single-string patterns, and as I believe @tommo has recommended, maybe some two-string patterns as well. Doesn’t have to be totally synchronized with the fretting hand, just has to be fast and fluid. You can clean it up later once you start to replace the stringhoppy movements that are holding you back.