Thank you. This is a spectacular amount of work and information.
As someone who is interested in similar old hardware that occasionally lacks any kind of documentation (specifically cameras), I sincerely wish I had this level of patience and determination (and also understanding, I'm not really a software guy).
I wish there was a law that all hardware vendors had to dump a sufficient amount of documentation if they discontinue a platform such that it can be emulated.
The litmus test can be done by AI code generation in a sandbox during the period they don't have to make it open.