I'm not a chemist, or a stylist, but here's what I found when I googled. You'll have to decide whether you think this is credible or not. Shea Moisture shampoos have Decyl Glucoside as the major cleansing ingredient. This thread
, specifically post #10, indicates that it will remove even silicones that aren't water soluble.
Also, though it isn't backed up with anything, the last comment from the author on this page
also says that it will remove all silicones. She says to shampoo twice for your initial shampoo to ensure complete removal, but that after the initial shampoo, continuing with a single shampoo in followup cleansings is adequate for complete removal. The commenter is the site owner and page author, and she's a naturopath. In my mind, naturopath isn't necessarily equivalent to having plenty of haircare /hair product knowledge, but it's perhaps better than just a layperson saying the same.