Moorea is a spectacular island.
There is excellent snorkeling not far from the Intercontinental. My group took a tour boat that made its first stop for a visit with the reef sharks. I would personally recommend going with a diving operation or hiring your own boat. The big tour boats won't let the snorkelers wear fins even through the area is not within easy reach of the reef below. They expect their guests to hang onto a rope. The second stop was in a shallower area for feeding the stingrays. This is the Polynesian version of Stingray City. There is also a motu, or small island on the north side of Moorea. There were a surprising amount of hard corals but not as many fish.
Sorry I can't help you with the whales. Enjoy your trip.