I need the data model/schema to use with ArcMap.
Like described above our recommended approach would be to leverage the ArcGIS Solution Deployment Tool in ArcGIS Pro. This will create the feature layers, maps and dashboard in your organization automatically. If you would prefer to do this manually you can follow the steps below to publish a new feature service in your organization using the template service we provide. After you do this you can export it as a file geodatabase and download to manipulate in ArcMap or ArcGIS Pro.
you need an ArcGIS Online or Enterprise account to Deploy this Dashboard. But I believe that PRO is required.
Follow this Help:
Retrieving data ...