The Caribbean is guaranteed four berths at the 2017 CONCACAF Gold Cup, and they have been filled by Curacao, French Guiana, Jamaica, and Martinique. But there is one spot still available to a Caribbean team: once the 2017 Copa Centroamericana (from which the top four will automatically qualify for the Gold Cup) is completed, the fifth-placed team will play-off against the fifth-placed team from Caribbean qualifying for a lucky-loser entry to CONCACAF's showpiece tournament.
To decide the fifth-placed team from Caribbean qualifying, there will be a three-team playoff in January. Trinidad and Tobago will host Haiti and Suriname in a round-robin playoff that will determine the Caribbean's representative in the Gold Cup playoff.
The games will be played January 4-8, with each team playing each other once. Haiti's first match is against Suriname on January 6. It plays host nation T&T on January 8. Win both those games (and it is assumed they will played under the rules of the Caribbean Cup tournament they are technically part of: no ties; extra-time and penalties if necessary to decide a winner), and Haiti will get to test itself against the fifth-best team from Copa Centroamericana.
The Haitian Football Federation has announced a 30-man squad for January's matches, including New York Red Bulls' Derrick Etienne.
The squad also includes Shelson Dorleans, who played for New York Red Bulls U-23s in the summer of 2016, but is not (as far as we know) currently formally attached to the club.
Thirty is a larger-than-usual roster for a competitive tournament. One would expect that number to be reduced in due course.
The January games are outside the FIFA window for international matches, which means clubs are not obligated to release players to Haiti. The matches are important: Haiti's senior men's team won't have a lot of competitive international soccer to play in 2017 if it doesn't qualify for the Gold Cup. But clubs don't always share the priorities of national teams. This perhaps explains both the apparent over-selection for the upcoming matches (perhaps not all players selected will be released by their clubs) and the decision to select a squad of mostly locally (or at least CONCACAF) based players.