keep in mind that the "MD>DO>foreign grad" idea does not actually reflect the quality or caliber of physicians... it's just the pecking order that we're referring to...
But, to be honest, a US DO degree is heads-and-shoulders above a degree from the caribbean and it WILL be easier for you to get residencies, in general. If you come out of a carib school with all high passes and ace your rotations, I'm sure doors will still open but it's more of an uphill battle... definitely more of an uphill battle if you're just average (not a small feat in med school, btw)
Best of luck! My advice would definitely be for you to attend WVSOM. I interviewed there and loved it. I am only choosing CCOM due to better clinical rotations in densely populated areas (more variety of exposure and diverse patients). You can't go wrong with WVSOM... and I am rather confused as to why you'd get an acceptance w/out interview if your stats aren't >28 MCAT & >3.5 GPA which would make you competitive at a number of other DO/MD programs. If this is the case, why are you applying carib?