Dilemna

Yes this is the correct spelling, at least within the Wittertainment universe. Both Mark and Simon were educated with the "dilemna" spelling. This was apparently due to a mis-print in a textbook issued nationally at the time the Good Doctors were being educated.

The discussion as to whether the correct spelling of the word is dilemma (as in the title of the Ron Howard film that prompted the discussion in the first place) or dilemna is yet to be finalised (or should that be finalized) to the Good Doctors' complete satisfaction.