We enabled NetFlow on the headend router, and I have created CVIs for each site. While I can see the CVI components in the PM inventory, and view their individual dashboards, I would like to have an overall dashboard that shows the volume leaders for the CVIs that are placed into a group and then allow the user to drill down to the individual CVI dashboard for further details.
You are looking to pull Flow data (NFA).
There won't be PM data for the CVIs.
So you are looking to build a group with NFA based data, which is not currently possible.