Configuring custom network in the Directions dijit?

I’m making a CMV app and trying to make the directions widget work with my own network dataset. I replaced ESRI’s street route network service with my own service, so viewer.js looks something like this:

directions: {
    include: true,
    id: 'directions',
    type: 'titlePane',
    path: 'gis/dijit/Directions',
    title: 'Directions',
    open: false,
    position: 7,
    options: {
        map: true,
        mapRightClickMenu: true,
        options: {
            routeTaskUrl: 'https://domain.com/arcgis/rest/services/my_network/NAServer/Route',
            routeParams: {
                directionsLanguage: 'en-US',
                directionsLengthUnits: units.MILES
            }                         
        }
    }

The app is not using my custom network. I get no results when using the widget–any suggestions as I troubleshoot?

I know the network service is working properly, as I got it to work in ESRI’s stand-alone example here.