You scored 16 or above out of 20. At that level your five domains are running, written down, and reportable. An engagement installs a system, and you already have one. Selling you a second would be the wrong advice.
A mature score is rarely even. The domain that scored lowest is the one place where the system still depends on a person rather than a process. That is worth fixing. It does not take an engagement.
Your profile names it under “Where a Diagnostic would start.” If you no longer have it open, reply to our email and we will tell you.
One Ambassador Day on that domain, bought on its own at $850. One credentialed Ambassador, up to six contact hours, on your site. No subscription and no onboarding fee.
Or nothing. If you close the gap yourselves, that is the outcome we would have aimed for anyway.