...and MANY thanks to you for your astute input.
Simple answer:
sudo vncpasswd -service
MUCH BETTER answer;
I have been fighting a few things, raspian/raspios 's weirdo (non-standard) setup and security models, along with realvnc's obtuse docs and it's default server installation that favors/requires the client also be realvnc while not supplying an aarch64 client that my manjaro-arm-aarch64 system could use. ( I am using tigervnc as the client on the Manjaro-aarch64 system. More on why "tigervnc" as a client at a later date.)
SO... I am working towards a MUCH BETTER solution, which is showing A LOT of promise. In fact it is already working much better than my previous solution !! SO....In the next couple of days I will be testing it on a new install, and I will write it up then.
Wish me luck om es vy 73 de "baab" w9ya