yikes - doesn't sound like a fun trip Eric
There are still some great DIY opportunities out there, at least you can really do what you want although the results aren't always better it would drive me totally nuts to have no choice of what to chase after.
As a guide, if the clients ask for a certain experience that I felt isn't the most promising I would accommodate as long as they understand the situation. Perhaps after a day or two one would acquiesce, but it would be your own choice and it sounds like they pushed you into doing what they wanted to do instead.
Puerto Rico is a great place for tarpon, but NOT the San Juan lagoon thing unless you want to squeeze a quickie in while you're near the airport. Look into the west end, Porta Del Sol where the locals go on their vacations. There are guides, but also boat rentals and lagoons with lots of tarpon and other species. I've seen permit in the 30# class as well, although was too occupied with the tarpon to change flies.
Bahamas bonefish, or better yet Hawaiian bones might change your mind about them too - I have heard those Mexi-bones are minnows.
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