Would suggest that you evaluate all weaknesses, and speak with schools (presuming you applied for this cycle) regarding add'l items that they may see as helpful - when I did this, 2 schools said that the feedback interview itself would be noted in my file and count as an indicator of my focus on that school, & would help with readmission process.
If the primary weaknesses are mcat section score(s), volunteer work, personal statement (anything other than that tough-to-overcome low gpa), it seems premature to only be looking at carribean - given the risk of possibly not securing a US residency if you go the carribean route, I'd think it would be less risky overall to study like heck, take out more loans, and try the mcat again. I bumped my score up when doing this in the 3-6 point range, well within the competitive range. Just takes lots (for me, around 2 months fulltime) of focused study time.
Probably not a big deal to stay in school if your main intent is to avoid beginning to repay loans; many programs require 9-12 hrs; time to look into a cheap state school, or take art history courses at a community college if the primary intent is to defer loan repayment for now; whatever would earn good grades and allow plenty of time to study for the mcat. I'd take at least a few more science classes in order to provide a good answer for "how did you strengthen your app from last year" in addition to a higher mcat score.
Another option to defer most loans is the "hardship deferral", particularly if you're not working, or earning fairly little due to study schedule, call the student loan folks.
I'd suggest against the master's program if the primary intent is to give you time to study for the mcat, better to kick *** in some science classes at undergrad level than spend the $$ (probably much more) in grad school. that's my $.02