There is another way to recover from a situation like this: connect remotely (e. g. via SSH) and issue a reset for the whole controller:
echo fe980000.usb > /sys/bus/platform/drivers/dwc2/unbind
echo fe980000.usb > /sys/bus/platform/drivers/dwc2/bind
It would be nice if the script does that automatically once it detects a missing keyboard in lsusb output.