

If I understand you correctly: You want to be able to record one computer with another one on a system level (the BIOS-party that comes before any operating system is loaded).
Although this is not Linux specific: your best bet is a video capture card as you’ve suggested already. Anything else would depend on your bios supporting remote access which is not exactly the same (my server bios for example can expose a website where I then can configure it from within a browser.
The problem with video capture is that you’d still have two controls: one for the client and one for the host.
Depending on what your final result should be it could be actually easier and cheaper to just get a stand for a smartphone and record it from there and then crop it precisely.
You then have to only worry about light reflecting.










You don’t! At least not in the sense that I’m aware of the JADE thing:
JADE is nothing that is a strong work proven topic but came from social media to handle narcissistic people as a peer group.
Your reactions are hostility and rejection based and how I understand you it’s your nerves that you want to preserve.
For this in a professional work place there are multiple ways to deal with and even all of them at the same time, just from the top of my head:
Hope this helps a bit!