Believe me or not, my pi was off since something like an hour, and as I was approaching my monitor to try your idea and unplug the screen, the Pi just waked up! Not far to declare it possessed by evil spirits...
@jmm_73 you can try multi switch script with --onoffshim parameter there is an option for latching or momentary button included. Please remove the Pimoroni script before and call the multi switch kind off sudo ./multi_switch.sh --onoffshim
