No, I believe they were a real audience. The sneeze trick looked like some sort of armature to keep the jacket in place. The head slide was just more of his amazing physical dexterity. If a magician/illusionist is doing his job correctly, he has you looking where he wants and when he wants. The trick is to watch where they do not want you to see. I have always been fascinated by magic and the way to figure it out when possible.