Hello Russ and thanks for posting!
The use of our Thunderbolt 3 dock within a guest operating system provided by a virtualized installation within VMware Fusion is not supported or tested. That said, we would expect only the USB ports of the dock to pass-through to the guest if connected in the manner you describe (the dock’s video outputs or Ethernet port would not be available to be used directly by the guest).
Thank you!
Bob
Plugable Technologies
www.plugable.com/support