I used to be a big supporter of brachytherapy. I no longer am. I had brachytherapy in 2020 and it failed in 2023. The Doctor who did the procedure told me that if cancer came back, it was an easy option to have surgical removal of the prostate if the procedure failed. That turned out not to be true and I only found five doctors in the whole US that could or even would attempt to remove my prostate after LDR failed.
Other treatment modalities, such as cryo- or HIFU might be better as in the case of failure, there is a no collateral damage of surrounding tissues unlike LDR brachytherapy.

You’re a low decipher score is a positive indicator that you might have these options for sure.

Good luck. Hope everything goes well.