So it would appear that I may have found a bug regarding Key_3 VNC Password, and am not sure if this could be an issue on the docker image side or the noVNC side.
I setup a password for Key_3, but when accessing the webgui I can get in with 70% of the password correct, or any combination of characters after the correct password. I have also attempted to change the password with similar results.
For example if I set Key_3 to Password123, I am able to get to the gui with Password or Password1234567890.
This isn't critical for my application and I haven't seen anyone else on here or the noVNC github with a similar issue. But it might be something to look into. If it's likely more of an issue with noVNC I'll post an issue on github.