Is there an ancient civilization there? Possibly.
Is it Plato’s Atlantis? I doubt it. I don’t see how the Greeks would have had contact with a civilization in Cuba and have no written record of it, given the seafaring technology of the time.
If there was an “Atlantis”, the Crete/Santorini theory seems the most plausible.
Atlantis, if it ever existed, would be in either the Sea of Azoz or Med. Sea of Azoz fits the discription best.