I can’t show an example of where he’s not using it, cus he’s not using it lol, he changed to a single anchor with his pinky, and his ring on the high e string, not used as an anchor anymore, and as far as I can tell usx with some alternative picking, I’ve never seen a video where he does true DSX like he did in his teens.
What he seems to be doing after the sweep is some alternate picking and legato, perhaps full alternate, hard to tell, but I don’t see DSX there.
It’s so obvious when he does pure DSX, here is the latest time wise video I’ve seen of him doing it. Great insight as well, mad flapping. Thats all you need with a single escape.
I’m sure without doubt he did it at times, but from everything I’ve seen this double finger supported dsx flapping vanishes from his later playing. And it turns into usx with alternate. Most the videos after this are from live cacophony videos, I don’t remember seeing him ever do this movement again. But if I’m wrong someone post it! 
I like how he described it as fake too, I think thats saying he was using legato a lot and not full alterate, alternate being viewed as the only legit technique at the time?