We ended up not going on the trip as the Blue cave was closed, which I totally understand is not tour operators fault, it's out of their control. The problem I had was a complete misrepresentation of the boat, it's nowhere near good let alone luxury. It's an old decrepit boat with meager seating. The boat depicted on their ad page seems to me false advertising!
Auf dem Ausflug:
Blue Cave with luxury boat - 6 islands and 2 caves