honeymoon on la reunion activity ideas

Hi all & I hope post belongs here…

My mom & stepdad are getting married soon and will go to La Reunion on their honeymoon. Since they both are the type of people who never need or want anything, my sister and I thought of giving them something related to their honeymoon or an activity there as a gift but not knowing much about the island we're unsure about what.

Has anyone here been there and had a nice experience with any activity or something they can recommend? Thanks for any advice!