Which one has all of the first neverwinter night Platinum or Diamond

Diamond is the most complete pack. Platinum contains Neverwinter Nights, Shadows of Undrentide and Hordes of the Underdark. Diamond contains those three, plus Kingmaker, Shadowguard and Witch's Wake.

However there are some additional premium modules that are as of today, unavailable, either seperately or as part of a compilation, not even in 'Neverwinter Nights: The Complete Collection'.