I'm not sure what the formalities would be in the shocking case of a meal that finished at the entremet chaud and omitted dessert entirely.

I'd complain loudly to all concerned if I were you. Spoon and fork in hand, drum on the table and chant "We want more" until you get your just desserts.

(NB: This may be a lie)

Which reminds me, I have several people I owe a dinner to (including you) and should really get around to organising something and finding out people's availability.