I am not on that type of visa, so never opened a bank account, but I believe many others on here have and have written about the hit-or-miss difficulties is opening an account with this letter. I believe people are successful at certain branches/banks. Maybe look back through this page and find specific branches and go there? Problem is, as you mentioned, do you have enough time now left on your tourist visa to process the retirement visa? My understanding is it takes a lot of time, so have to do everything very quickly.
Curious, what type of visa did you already apply for, that you received wrong information? Did you not qualify for that visa or didn’t have correct paperwork?
I see. Was just asking, because it feels like people are having an easier time with Laos, Cambodia and Vietnam, all of which are closer. However, if you were already planning on going to HK, that makes sense.