I note that the picture of the physical switch actually shows a fifth solder connection - between 1 & 2 in your picture - and I observe that this is soldered on my Expansion Dock
I still don't understand just how this all works and how the switch is actually connected. @Lazar-Demin above says that the RESET_BTN is connected to ground when the button is NOT depressed. I still don't see how this works given the circuit diagram and your description of the button
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