Your daughter wants to go into a hot tub with a tampon on i am not sure if that is a safe thing for her to do?

I'm not sure why you would worry that this is not safe.

Tampons generally aren't safe but as long as she is following precautions her risks are reduced, going in a hot tub while wearing a tampon isn't going to increase tampon risks. Girls go in hot tubs all the time without a problem, there's no reason to think that this would be a problem either.