Great find, only one point of contention- The DUmmies are all old, ancient, WAY older than Mad-Libs, although the pun you've got there is great. Calpig, for instance, will have no idea what you're talking about.
Ancient DUmmies like Calpig will be more familiar with the great-grand daddy of your game, and the name they grew up with: An Account of Peter Coddles Visit to New York (1890).