Hello there, @dso0216.

I appreciate you for sharing the troubleshooting steps you've performed in your end. If I may ask, have you tried using a different email address in sending the accountant invitation? If not yet, please do so.

If the issue persist, I'd recommend sending a message or scheduling a callback with our Customer Care Team. A specialist will be able to further check on the root cause why you're unable to received any accountant invitation email. 

Here's how:

1. Log in to your QuickBooks Online account.
2. Go to the Help menu.
3. Click Contact Us.
4. Under How can we help?, type in any keyword about your concern.
5. Hit Continue.
6. Click Get a call back.

Stay in touch with us here in the Community if you have other questions about sending accountant invitation. I'm always here to help.