Hi Justin,
The app displays that message when it finds no precincts at the address' point in the PrecinctLayer service or a webmap's precinct operational layer. And this stops the processing, so no route is generated.
In order to make webmaps easier to use, the app makes the crucial assumption that polygonal layers that have a popup are tested for elected officials data; the layer without a popup is used for precinct boundaries. If you're using a webmap and all layers have a popup, I believe that this would prevent the app from identifying the precinct layer.
Regards,
Mike