The printTaskUrl and geometryTaskUrl parameters are ignored when set in the constructor of the Directions widget if the TaskUrl route is set to any URL besides the default.

Solución alternativa

1. In the constructor of the Directions widget, set the printTaskUrl and geometryTaskUrl to the desired services. Set the routeTaskUrl to: 'http://route.arcgis.com/arcgis/rest/services/World/Route/NAServer/Route_World'
2. Add the following code block to the application: directions.on("load", function() { directions.routeTask._url.path = <url to your route service + /solve>; directions.routeTask.url = <url to your route service + /solve>; directions.routeTaskUrl = <url to your route service + /solve; });

Pasos para reproducir