Thank you both for your recommendations, I appreciate it. I am looking at those providers and considering them.
If anyone can continue to provide me recommendations, I will be staying in a hostel in town, so I'd like to find a place that is either within walking distance, or that provides transportation to their launch site. Tres Pelicanos does look to be within walking distance.
Two places I have seen that are "dive hostels" are 2tanks dive hostel, and beds friends hostel. They both have their own diving operations. 2 tanks has not responded to my emails so I don't think I'll go with them. The other one has the diving op "Cozudive". It has good reviews if relatively few of them on tripadvisor. Has anyone used these places?
Hopefully my research can help anyone else with the same questions. I'll certainly post who I go with and my experiences.