Google "Grant Access" source stays on "Setup needed" — what are we missing?

Hi all — hoping someone can point us in the right direction (very likely something on our end).

We're stuck on the Google Grant Access (Sign in with Google) flow. The core issue: after the customer signs in and approves on Google, they're never sent back into the app or the dashboard at all — the browser just lands on their own Google account page. Because they never come back, the connection never finishes: the source stays on "Setup needed" and no reviews are ever pulled.

(Public / place_id import works perfectly — it's only the Google sign-in path that does this.)

We've reproduced it many times, including with a few friends using their own Google Business accounts — same behaviour every single time.

Our custom primary domain (a subdomain, agency setup) shows fully verified and active in the dashboard — DNS, SSL, all green — so we don't think it's that.

Any idea what we might have configured wrong? Happy to share a test account privately so it's easy to reproduce. Thanks a lot!

Manu

PS — @mannie@embedmyreviews.com, sorry to tag you directly and I know you're slammed — but if you ever get a spare minute, your eyes on this would be gold. Absolutely no rush, and thanks either way! 🙏