Dave,Modification: _IF_ the vehicle is still plugged into the external charger (EVSE) one might consider removing the charging plug - since the vehicle is "dead" this will require that you access the manual release pull cords - please see Porsche's "good to know" information for these instructions.
Since we're dealing with electricity - safety pre-cautions should be taken and having a live power source plugged into he vehicle may not be the best plan...
this is an extra measure of safety - since in the US the J-1772 power requires a vehicle to be "alive" to talk to the EVSE - the EVSE should have cut power when the vehicle died - but better safe than sorry.
Nice write up and I hope I never need to use it.
Re: if charger still plugged, why not unplug the charger from the NEMA 14-50 or alternatively disable the circuit from the house fuse box? Seems easier to do than the chord release