Damar and Dukat only got given names in the lit-verse (unless I'm mistaken).
You're correct, although Dukat's initials were revealed in A Time to Stand as SG. He refers to himself in his log as "Dukat, SG" which would be consistent with his first name of Skrain given in the novels.
However, someone. Ira Behr or Ron Moore or someone said that the original intent was that SG was meant to be an abbreviation of his title, "Station Gul."