Whoa! Like you can’t even connect via serial or get the white button to work (?!?)? This is most likely either hitting 100% CPU usage or a kernel panic, in the 100% CPU case I would expect you to still get a screen session eventually. Might want to work on this kind of thing with an SSH or serial connection open running journalctl -f or dmesg | tail -f to keep an eye on system logs. If you are in fact getting a kernel panic I expect the panic to dump logs to the serial TTY no matter what else is running, though it’s possible that an SSH session would die.
