The best waterproof camera I’ve had is my Olympus Tough TG-860 with its flip screen.
It was replaced by the stylus tough TG-870
But I don’t think you can get them new anymore. Mine is 6 years old and still takes great pictures so a secondhand one might be a good option for a TG-870.
The TG-6 takes even better photos but it doesn’t have the flip screen and it’s a bit heavier. A much better all rounder camera, but for a specific fishing camera I’d try and get a TG-870
Sandy