Look, this is such a great idea. As for the camera, I'm unlikely to tell you something, but it sounds very cool.

It will really be a very cool gift, especially for a person who regularly dives under water. I think you should check out the article, which has 9 best snorkeling camera options. By the way, from this article, I learned that the gopro is not the best option, although I used to be sure that this is the best camera for such action shootings.