Is "partial" SSO possible?

I am excited to see the compatibility feature between SSO and invites but it does not seem to work on my end.

My main site is on WordPress and I am using the WP Discourse plugin to integrate the two applications. I also have a registration form that conducts email authentication on WordPress and I have written custom code to prevent Discourse from sending duplicate verification emails to users on registration. I have enabled must_approve_users in discourse to prevent anyone for accessing the community without approval.

I followed the following steps and user was not approved in the end. Just like before.

  1. Invite user with the email address
  2. User opens the email invite and click on the link
  3. User is directed to the discourse logged out page with a welcome message and CTA to continue
  4. Clicking on the CTA takes the user to the login page on WordPress
  5. As the user is not registered on WordPress, I had to create a new account for the user - which I think makes sense since WordPress does not know that Discourse invited this user.
  6. After registration, I receive a confirmation email from WordPress. I click on that email and I am directed to the login page in WordPress.
  7. After logging in WordPress, I try to the community but I cannot.
  8. I go to the admin account and check the status of the user and as I suspected, it is Needs approval. This is exactly the same situation I had before sending an invite.

What am I missing here? Is there some other flow I need to follow? Can I only invite users that are already registered on WordPress? Looking for some guidance here. Thank you.

My Discourse Version: 2.8.0.beta1