I have had trouble in the past when updating the OS and the machine hanging and then shutting down. When it first happened I thought that the machine was finally done. But plugging in devices, particularly a Thunderbolt cable to an external hard drive (though I think I may have also used regular USB for other external drives on other occasions) kept the machine from going through it’s random shutdown and got me through to being able to use NoCrashMBP. As you may have read people use HDMI cables plugged in and have had good experience. Don’t know if this will help you. I finally gave up on the renaming, just too painful now with Big Sur and just use NoCrashMBP and pay the price in shorter battery life. This has been a very painful exercise for a few years now for me. It’s hard to believe Apple has never acknowledged the problem or provided a real solution.