Yes there is this in Maldives and have been for a while. They have a couple of executive style rigged Twin Otters that is also air conditioned. The seating is also much better like a private jet. A s for the lounges in Maldives a lot of the Lounges are owned by the resorts and also the longes owned the TMA and Maldivian is also very good. Just like commercial lounges in the airports.
These aircraft are used by the resorts on special charter and not on the normal flights they use daily. Both TMA and Maldivian use the executive styled twin otters.