I am not understanding the criteria for this quiz. Firstly, please explain your justification for apparently requiring the word "island" to be added in some cases but not others. Secondly there are some obvious errors. New Guinea is clearly the largest island occupied by Indonesia and by PNG, Hispaniola for Haiti and DR, Cyprus for Cyprus and Borneo for Brunei and Malaysia, yet all these answers do not score. Why not?
TL;DR a country must fully own an island to be included in this quiz, so countries that share islands, like Hispaniola, do not count.
Island being added in some cases and not others is just me being lazy and not making type-ins. I will fix that later.