I posted some additional details of the resetting process for those that are new to this. Rereading my steps; 1 and 2 should be swapped but the process of pressing and waiting for the RED LED is the same.
In the event your machine is already in the powered up state, (i.e. power button is lit) I am fairly sure this will not work.
If the EC is in a panic state it may try to autopower on as soon as a charger is connected in an attempt to clear or migrate its state to a known stable one. I have written code in the past that did just that; though this was in the late 90’s.
Once you connect the charger, wait a good 45 seconds to make sure it is not powered on and for any subsystem to enter a steady state.
Summary
If your power button IS lit, press and HOLD it for a good 20 seconds. This will force the EC to enter a shutdown state.
If it truly is all scrambled, you may need to disconnect the battery, then try pressing the power button (I know it sounds dumb but it will clear any residual stored charge), then reconnect the battery and try to boot the machine, before trying to reset the mainboard again.
I am trying to not talk out of my @$(^ here; just trying to suggest some tips to bring your FW16 back to life.