Kim--I have no idea where it sails from, but if they are going on Sea Cloud, I don't think they would be happy with Sea Palace.
My recommendation would be Le Petit. On the beach in Grand Case. Along with it's sister hotel, Le Esplanade, easily one of the best hotels on the island. Esplanade is not on the water though. Le Petit does not have a pool, but Esplanade does and I believe you can use the pool at Esplanade if staying at Le Petit. Grand Case Beach Club is another good option, but I personally don't care for the decor there now, as they re-did the hotel with a much more modern feel. Le Petit has a much more classic feel.
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