I'm Colombian and in January I will be doing pretty much exactly the same thing you plan to do. When I got my visa I got a double entry tourist visa (in the top right corner of the form it asks you to write how many entries you need), which costs twice as much. If I were in your shoes I would not risk it and definitely would go to the consulate and get another one, is a one-business day process in NYC, so I guess is similar in Miami. It's gonna use an extra page of her passport but you won't have to stress about the re-entry permit.