I agree that it's Mauritius, but the auction is for Sofitel So. All the details fit (even tho the regular price is a tiny bit off--$16 difference).
Still, a very nice deal if it stays under the usual auction price.
I also believe it's the Sofitel. With such a beautiful destination, great reviews (5 "dot" TA rating) and such a high quality brand, I'm sure an amazing honeymoon is in the making...