Urm, what? If the MeeGo project says MeeGo UX (Components) is required to be compliant, then yes, it is required to be compliant.
Harmattan is not MeeGo compliant, Nokia know this, MeeGo community know this, and you should accept that. Now, Nokia want a waiver from the MeeGo project to (falsely imo) have permission to state that Harmattan is MeeGo compliant, it isn't we all know this but Nokia are arguing that it's acceptible in this case, because they both have compatible Qt APIs which is where most developers will live.
Using DUI wouldn't break compliance. Why would Nokia use DUI? Because Harmattan, for the last f'ing four years has had DUI. That was the whole point, Harmattan step 5/5, DUI replacing Hildon.
Especially Nokia? Are you ******ed? Qt Components is being developed in the open, it was MeeGo UX that was behind closed doors, both are open now.