Well, it is weird. I do have the gnome-screensaver. I have the original script in place. It doesn't seem like it worked right in testing, it definitely seemed as though any interaction using putty was making it less predictable. Even taking that out of the equation, after shutting down firefox, the script properly changes idle_activation_enabled setting back to true, but then the screensaver doesn't seem to come back on.
Then I gave up with it in that state, next day I noticed the screensaver seems to be working. So I guess it is working.