My take on the receptacle is that it's unrelated to the event. We see it all the time in high current appliances, and it's really prevalent in the RV world at the shore power connections. The blade to socket connection isn't the best thing and it will overheat and melt the surrounding plastic.
It was likely already in the process of overheating and just got noticed when this event happened.
It was likely already in the process of overheating and just got noticed when this event happened.