We did a bus to boat to Haitias tour with lunch at Bacardi Island.
The tour was well organized. The guides were fluent in Engish, French, Italian, and of course Spanish.
My family got got the guide speaking English and Italian. The larger group got the guide speaking French. There wasn't a Spanish speaking group.
We traveled by bus from Las Terrenas to a dock in Samana. Then by boat to the Haitias coral formations in the Samana bay. That was the best part of the trip. After we traveled by boat to Bacardi Island, an all inclusive resort island, had a meal and had 50 minutes to snorkel. From there we went back to the boat and then bus and back to Las Terrenas.
I missed being around Dominicans on the trip (only one guide was a native Dominican), but very much enjoyed seeing the coral formations and the caves and cave paintings in some of the formations.
If you can afford it, you should go.