Because the outlying villages would have had their own temples, palaces, storehouses, etc. There would have been ruins that could not have been attributed to the Taino or Arawaks when the Spanish arrived.
Well, the answer to your original question is “Maybe... Maybe not.”
1 - Maybe there was only that site made of durable construction
2 - Maybe there was more but it has not been found
3 - Maybe there was more but it was destroyed
I certainly don’t question Pompei because there are no similar structures on Mt Vesuvius.
Regardless, the suggestion that the absence of similar finds nearby invalidates the one find seems illogical to me.