Great story, artfully crafted. I really like your writing style.
As for your conclusions about the man, my inner jury is still out. People are complicated and contradictory, and a high percentage of our behavior is opportunistic rather than planful.
So it could well be that he saw you first as a romantic/sexual opportunity, genuinely enjoyed your company and liked you as a person, and only later chose to try to squeeze some money out of you. Not saying that's what happened--you're in a far better position to judge that--but it would be perfectly consistent with the story as you've told it here.
In any case, thanks for sharing a fascinating story. I'm sorry Costa Rica didn't agree with you. I just fell in love with Guatemala and will be returning soon for an extended stay.