I did see something called Intel AMT, part of Intel vPro. https://www.howtogeek.com/56538/how-to-remotely-control-your... Does anyone have experience with this? (I have AMD box so doesn't help me) - actually looks like AMD has similar https://developer.amd.com/tools-for-dmtf-dash/
1) https://www.adder.com/en/kvm-solutions/adderlink-digital-ipe...
You could build ~7 devices for as many machines using the article's method.
So I only wanted to point out that there are good solutions out there, even though they might not be cheap. The solution have saved my bacon, and has been worth the money.
Looking at the original project, authentication, mouse support and audio are not supported (maybe in the future?), so if those things are important; a solution like the ipeps might be worth it as well.
But your mileage may of course vary . . . :-)
Edit: Grammar