This really is likely the best tour, book it! There are a dizzying number of tour guides, but who you go with matters. If you like to avoid crowds, go to hidden gems, travel with a knowledgeable guide who is fun to be around and takes care of the environment, this is the right tour.
Some cenotes are parks. Commercialized, lots of people, highly developed property, etc. Similarly some tours will have a bus load of people. Those are just a completely different experience than this tour with Juan which goes to more secluded places with just your private group and I highly recommend it.