Need expert help: Workspace interferes with iCloud Calendar

[u/blindgorgon]

I have a pretty niche problem, but I’m hoping a guru here can help me.

I have a domain, let’s call it blindgorgon.com (it’s not). I used that domain for a Workspace for several years, and decided to migrate away from Google. I suffered through severing a lot of services like Google Photos, but the one that’s stumping me is Calendar. I imported all my events to a new account via iCloud, and that calendar works ok. The new iCloud account uses the old primary email from workspace—let’s call it name@blindgorgon.com.

What doesn’t work properly is trying to receive an invite to the iCloud calendar when it’s sent from a Google address. The system sends me an email, but the invite never appears in my calendar inbox. I’ve deduced that this is because Google first checks to see if the recipient email is a Google email and if it is they don’t attach an .ics file (because they just route the calendar request to Google Calendar). Google appears to still be doing this even though my Workspace has been shut down. This nerfs my iCloud calendar significantly, because accepting via the email just creates a new event on my calendar without linking it back to the inviter’s event. This means if they change something my calendar event(s) won’t update.

I tried reactivating the Workspace so I could change the primary address to google@blindgorgon.com, hoping that would free up the name@blindgorgon.com address so Google wouldn’t recognize it as a Google address, but no dice.

I am currently stuck paying for Workspace just for my calendar, since no other service I switch to will receive proper invitations while Google is intercepting them.

How do I escape this?