I remember this page. We printed it and had it, but I don't remember anyone asking to see it or anything at the Embassy. When we arrived, they asked our last name and checked on a clipboard and let us in. Then we waited until they called us up to the window and turned in all our paperwork there. No one ever asked for the reference number or anything.
Based on my experience, I'd say you'd be fine. But better safe than sorry--you might want to call and check.