they say use the first letter of the item, it is not called a nemo organ. You can always hit the shop button to see the correct full name for an item. I too had 2 of the same letter for a minute when i thought the Karo tiki chair was just a "tiki chair". But then i looked it up.
so lets see we have
1. Tomorrowland sign
2. Underwater organ
3. Rhino
4. Karo tiki chair
you should not be confuzzled anymore lol