drivencompassion maybe I've misunderstood what you want to achieve. Tell me what scenario is your case:
- Flarum on root, WP on subdomain --> WP as SSO system
- Flarum on root, WP on subdomain --> Flarum as SSO system
Case 1: This is possible with the SSO extension. Just configure it to your URLs
Case 2: Not possible with the SSO extension, since it's the reversed case
In every case you can't have more than one SSO system linked to Flarum with my extension and the Flarum domain and SSO domain must be the same to get cookie working (I'm talking about domains, not subdomains).