Your Haitian Fiancee needs permission from the US government to allow her to enter the USA. This is called a K1 Fiancee visa.
Fiance visa applications are held only briefly at NVC, just long enough for NVC
just long enough for NVC to assign a Port-au-Prince case number and forward your file via diplomatic pouch to Haiti.
Once her petition arrives in Haiti, the consulate will contact your fiancee advising when they have scheduled her interview.
Two weeks before her interview date she undergoes a medical exam at an approved Medical clinic in Port-au-Prince
Finally she attends the visa interview at the consulate in Port-au-Prince, to demonstrate she is of good moral character and the engagement is Bona fide.
By Fred Wahl
Your Personal Immigration Guide