Success at last.
I got my RPi configured with dynaframe (for the slideshow) and rclone (for google drive sync). I have tested it with my own google drive and TV. It works very nicely. The slides gets updated within couple of minutes of me adding or deleting files from my google drive folder.
Please let me know when is a good time for us to install in on the Lobby TV. I need to remove my google drive account and add whoever is going to manage the slideshows.