Sure! How about we have an outing, to a park or a theater or a aquarium? Having them talk in more public surroundings. Maybe even have it there that the person spots Zach and gets the first inkling of his story not being true. It could be a street kid, or perhaps a church patron, but they do not bring it up until later, when out guys are a little closer? (By the way, out of all those options, I like aquarium best :P)