As others were saying, the developers actively wanted to exclude disclosure the flood status of these plots to potential buyers. Eventually the city "compromised" with them to hide a one-sentence warning deep in the paperwork.

Now granted, this did not prevent the homeowners from doing their own due-diligence, but I really think that the city officials that agreed to this, and the developers that lobbied for it should all be taken to task for their actions (and I think this regardless of what happened during the hurricane).