Brilliant Guide. I've finally got Frigate running with a Coral USB! after 2 years!
I needed to add this path though
/usr/local/tempio/bin
addpath /usr/lib/btbn-ffmpeg/bin
addpath /usr/local/go2rtc/bin
addpath /usr/local/nginx/sbin
addpath /usr/local/tempio/bin
then it worked