Unexpected shutdown

I have a 2017 MacBook Pro which has recently started shutting down with a Panic Report when I'm using it for video calls (Meet, Teams, Zoom etc). It was running Mojave at the time. The local Genius Bar did a lot of tests and found no hardware issues, but did find a battery firmware fault so they wiped the whole drive and installed Monterey. The shutdown is still happening, maybe 20/30 mins into a call. I notice that as soon as a call is started, the CPU usage goes off the scale (well over 100%) and has reached 200% before the Mac decides enough is enough! So I suspect something to do with the camera software.

Does anyone have any ideas or advice, as during the pandemic online meetings have been a life-saver.

Thanks