External wakeup from deep sleep on XIAO ESP32C3

@Dean_Arnold - I have tested a system with the keypad I have here rewired to operate with the same keys you have on your keypad.
It works well, with a 35mA operating current (irrelevant really) and a 14uA Deep Sleep current.
As suspected the “middle row” doesn’t wake the device, only the two “outer rows” where the RTC GPIO’s are connected.

I also added a “jumper” wire (soldering) from GPIO 7 (D8) to GPIO 43 (D6) to get a full keypad. Since you are soldering the battery terminals and pin headers anyway, it should be an easy enough addition. If you don’t want to use another GPIO pin, a 10k pulldown resistor will do the trick (also tested OK).