If you're using the two StoreVirtual 3200s in a scale-out or stretched cluster, you'll need a license for the Advanced Data Services. There's not additional licensing for the FOM. Here's a ChalkTalk I did with an overview of the StoreVirtual 3200: https://youtu.be/cmBdIwwnjXQ
Here's also a podcast I did with the 3200 Technical Marketing Manager that dives a bit deeper. You can find the podcast on my blog: https://community.hpe.com/t5/Around-the-Storage-Block/Deep-Dive-Podcast-on-the-HPE-StoreVirtual-3200/ba-p/6953125
I don't believe the NFS file quorum witness is supported with the 3200 - only the FOM is available today.