If I may add a few thoughts which may spur other thoughts, acknowledging your head is already full. Being prepared is good.
Sometimes they tailor treatment by age. 64 might warrant a more aggressive approach. Hormones alone must seem to you they could do more, bearing in mind the quality of life issues others have mentioned.
I recall thinking I'd still want surgery whatever they found nearly 6yrs ago, although now I'd accept a full dose of RT instead. I did look up private options and RT is very expensive. However I had surgery and was told they wouldn't offer it if they thought it wouldn't be curative.
So this is probably very optimistic on the NHS but another writer on here surprised me when her husband was offered a trial on aggressive treatment recently. I think he was quite a lot younger.
An aggressive treatment could be a psma scan that may show whether there is anything else of substance. If there is nothing else then focal treatment to the spine, followed by radiation mainly on the prostate but also to the other lesions if they're all in the abdomen area. As you've already found, a triple dose of drugs next. That would be aggressive.
People have said on here that removing the main lesion has been found to be beneficial.
I noticed what Chris wrote above and perhaps he read the recent article about unqualified people on the internet not having the depth of knowledge needed. Then again I've met people of status who remain resolutely within a constrained zone. Hopefully you can ask some gentle questions and what the doctor says will make more sense with your increased knowledge. All the best Peter