Some folks might come up with Dominican Republic, I suppose. I can't imagine many people would come up with Djibouti, though some might.
I dont think it's weird at all. Actually the chance to get the 'Kangaroo in Denmark eating an Orange' answer is pretty high. Like you said, after you multiply a single digit number by '9' and then add the two digits of the result together, the number is always still '9'. And then after you subtract '5' from it, the final result is always '4'. Therefore, the first letter of the country is always 'D'. How many country names in the world begin with a 'D'? Not many. I can only think of Denmark, Dominica and Dominican Republic. Unless you are from South America, Denmark would be the most probable pick. Now, how many animal names begin with a 'K'? Again, not many. I can only think of Kangaroo and Koala. Majority of the people would pick Kangaroo. Lastly...fruit's name beings with an 'O'. What else other than Orange? Therefore, I think there is at least 70% of chance that you would come up with 'Kangaroo in Denmark eating an Orange'.