I think you need to see an oncologist before making a decision - they will be able to check how much RT you actually had and also what the implications would be of more RT to the area - might leave you needing at least one ostomy anyway. If you can see an oncologist who also knows about HIFU, cryotherapy and proton beam therapy, that would be ideal - these can sometimes be given as salvage treatment and a surgeon wouldn't necessarily be up to date on these alternatives.
If the onco says there is no alternative to surgery or long term HT, and you decide to go for the HT option, you will want to be under the care of the oncologist rather than a urologist anyway. Long term HT is not as bald an option as the uro is suggesting - you might be advised to have early chemo with the HT, or dual therapy of HT with apalutimide or enzalutimide or even chemo with HT and apa. The average might be 5 years but we do have men here who have stayed well for 10 years or more and chemo can be given more than once if you respond well.