I had a similar issue to yours when I manually ran this update on my 16". It froze on a black screen, after doing the BridgeOS part of the update. I had to force it down. When it started, it continued the update and, thankfully, everything worked.

However, I'm still having kernel panics after the Supplemental update. But interestingly, they only happen when the machine is supposedly sleeping, with the shell closed. I kid you not. I will have it sitting there on my end table in the living room, shut for over an hour, and all of the sudden it will reboot with the lid closed (I know because I have the startup chime enabled). I've never had a Mac kernel panic while supposedly sleeping. This is so f*cked.