First off, let me explain my setup. I am using Cloudflare with flexible SSL and forcing SSL for login and admin pages.
I have to set the Verify domain's DNS settings to NO. And when I add a domain, the health status will report as "invalid" even though everything is working perfectly. The mapped domain is properly forwarded to the proper site.
I assume the test tool is not handling the Cloudflare SSL correctly, and is reporting the invalid.