I only skimmed this topic, but is there a reason why you're not using the Zooz Garage Door Opener app that Zooz had written specifically for the ZEN16?
It has a built-in feature that ignores duplicate commands so if you have Alexa turn off a virtual switch and a rule execute the close command of both doors, that command should be ignored for the doors that are already closed.
Did I completely miss (using the zooz app and driver) in your original post or did you just add that?
Either way, I probably shouldn't have replied at 4am so after re-reading your post I now see that the issue is basically that you can't sync the virtual switch back to the device without re-triggering the door...
The easiest and most reliable solution is to add the switch capability to the Zooz Garage Door driver so that Alexa sees the garage door as a switch instead of having to use a separate virtual switch.
These are the 3 changes you'll need to make, but I don't see any downsides to them so I might make them to the original code at some point...
Alexa will see both as switches so you should be able to get the on(open)/off(closed) status of each and turn them on/off independently, but also group them and control them together.
If the doors aren't in the same state and you control them together, only the one that's not already in the new state will execute the command.
I didn't test those changes so feel free to PM me if you run into any issues...
So the change that @krlaframboise suggested seems to have solved what I need. I can now have routines with Alexa that don't require a passcode. And the switch is in sync with the garage door. Thank you @katsrevenge for all the help. Anyway to get the switch to show up on Google home?