Hi and welcome: sorry you and your husband have had to join the club that no-one wants to be in!
Unfortunately, some diagnoses can be a little vague (mine was, as by the time I was diagnosed the cancer had spread widely), and the oncology team can only work with the information they have. The good news is that the hormone- and radiotherapy will target the primary tumour in the prostate and this, in turn, impacts the metastases too.
I would think they'll start the treatment and will closely monitor your husband's PSA to ensure that it's having the desired effect. They can then adjust treatments, or add them, as necessary.
Wishing both of you all the best: right now is a horrible worrying time but the fight-back starts here! If I may offer one piece of advice that I've found increasingly wise: when I was diagnosed back in 2019, I asked my oncologist a zillion questions about treatments, etc. He answered very patiently, and added: "It's important to remember, don't make your life all about the cancer. Remember to live as well." He was, and is, absolutely right. Have the treatments, do the right things, but don't forget to do the things you enjoy too.
Craig