I just wanted to give an update. I was able to devote some time to this, and redesign the query. Along the way I had to make some corrections within WFA and DFM.
1. WFA by default doesn't pull the cifs shares on the 7 mode data sources. - You have to enable the acquisition under Designer -> Dictionaries
2. DFM wasn't pulling the export data properly from the 7-Mode filers. I had to fix configurations on some of the filers within DFM. (Without doing that some of the volumes would show up as not being used)
Finally, Attached was the query that I have re-writen since my original post.
DISCLAIMER: This query is provided at NO guarantee. You should manually check your volumes outside of WFA before making any action based on the query I provide. This query is only to assist you in not shooting yourself in the foot by accidently offlining/destroying a volume that has something currently active.