I’m not clear what a “double inversion” is meant exactly to be, but it seems to me what prevents a basic inversion in the given examples has nothing whatsoever to do with the “presence of an essential complements” (of which the “object” of II is one, by the way), but rather that the subject is expressed fully rather than by a pronoun, otherwise we get, with (if I understand the terminology correctly) simple inversion:

Avec qui va-t-elle à cette soirée?

and

Quand apportera-t-il le paquet?