Hi there:
Normally you can't switch between TV and PRV, but I found a way:
1. Open PRV in Multidock
Now you have Focus in PRV and you can Zoom with Ctrl+(L,R,U,D).
2. Press Ctrl+TAB
Now you can Zoom in the TV, but you have no possibility to get the Focus back to PRV
3. Open a second TAB in the Multidock(Staff View), so that you have 2 Multidock TABs.
Now you can switch with Ctrl+TAB to the Track View and Zoom TV, switch to the Multidock wit