Dear individual;
I gave you the wiki site because it was convenient and in this case accurate.
There are various books out there that support this understanding of Haiti as part of Latin America, including any older version World Fact Book or World Almanac published prior to the 2000. (I have not looked at one since so I do not know if they still use that category).
I was not giving you my opinion, as I don't care either way. And if you do or do not agree with the definition, that is entirely up to you; however, the fact remains that the language factor (in terms of languages with Latin roots) is what is used to classified Haiti as part of Latin America.