The RCI guide I spoke to earlier today said yes, a NOLA xchange would be covered, since the event hasn't happened yet.
Last time I bought insurance based on the fact that both RCI Guide + Berkely Care told me that yes, I would be covered in my circumstance, my subsequent claim was denied. So I don't put much credence in her representation.
But, you can buy it today, and have 14 days to cancel it and get a refund. So you theoretically have nothing to lose. That's what I just did. Tomorrow I may call Berkely Care and see what they have to say. Not that their phone reps can be trusted to speak the truth either, but I still have 14 days to gather opinions/evidence one way or another, and then chase my refund, if I choose to spend the time.
Edited to add: They (RCI and Berkely Care) will let you - in fact encourage you to - take out the insurance, and are happy to take your $$, after an event but before you or the resort or RCI knows whether your resort was damaged and if so, how long it will be closed. They just won't pay the claim.