We had the same problem in Miami last July on the way back from Curacao and then this past January on the way back from Port of Spain. We got the X the immigration lines went fast. When we went down to custom to pick up our luggage to recheck to Houston it was at least 2 hours wait. The lines were long and there was no order everyone was cutting and total chaos. We decided after that to get global entry it’s good for 5 years. As our route from Houston to and from the Caribbean is thru Miami .