You're right. The article itself does focus on dissolving oils. But what I meant by the author implying that cocamidoproyl betaine might not remove all silicones was based on his or her answer to a question in the comments section.
It seems that the author is saying that silicones are similar to polyquats in that they need the harsher sulfates for removal.
But even if that's true, that would apply only to the non-soluble silicones. BTW, I'm not necessarily agreeing with the author but was just pointing out to the previous poster that Natural Haven, as far as I can see, doesn't flat out state that cocamidoproyl betaine removes silicone build-up.