I think I figured it out! Here's how I fixed the Purge_Fences invalid uninstall control file problem:
In C:\Program Files (x86)\Stardock\Fences\ I deleted 1xuninstall.cmd
I then deleted this folder: C:\Program Files (x86)\Stardock\Fences\Uninstall
I then re-range Purge_Fences.bat. It still gave me an error message, however at the end, Fences was actually removed.
Afterward I was then able to install Fences 3.09.