We had some issues with Google Apps integration as well when we upgraded to 2.x, but they were slightly different. Everything worked fine, but we figured out that Google accounts were not automatically created for users until a user went into their Moodle and updated their profile (or an admin could update each users profile individually). This could be them updating their password, adding info to their profile, etc (or you could just press update without updating anything and it triggered the creation of the Google Apps Account).
It looks like our Moodle is no longer using Gsaml and there is no longer a Google User Sync Block. Our host is using Google OpenId Authentication. I wonder if using Google OpenId Authentication will fix issues or cause more... Any thoughts?
Thanks for keeping me updated on your results. I really appreciate it!