I hadn't thought of slipping the Doctor in there on her! Neat idea! Could very well have been, though - who knows who that waiter was. Funnily enough, I have an unfinished work in which the Doctor does just that to someone - passes by as a busboy. After he goes back to the kitchen, the character in question (an OC who doesn't know the Doctor) asks her friend, "Since when do busboys wear suit and tie?"