My only dolphin experience was Blue Lagoon near Nassau.
Again, check Tripadvisor. The top rated one in Cozumel is at Chankanaab Park. If part of your party is not interested in the dolphin experience, it is an okay place to hang out. I visited when the weather was too choppy for my booked excursion. (I haven’t found my sweet spot in Cozumel yet).
And look at Shore Excursions Group for experiences (and associated reviews). This and Viator (part of TripAdvisor) are reputable sites for booking. I know Viator has Book Now Pay Later option (card gets charged 2 days before excursion. This is helpful with other cruise lines, as those often charge you on booking, unlike Disney’s system).