My Power Transfer Switch is located under my front dinette bench. It's in a steel box. I hope that would be enough. I do store my heavy maintenance supplies in that bench to distribute the weight better, things like tools, jack, and cords, but no flammable liquids there. Something to ponder.
Sorry to hear you were scrutinized like that. Insurance companies can be your friend or your foe.
That chirp and loud click we all hear when powering up our rigs by the entry door activates a battery Isolation Solenoid, located behind the bottom doors under the fridge in our 2007-2350. That thing worries me because we had one in our first motor home that went bad and nearly caught fire. It was located under the hood, used to switch batteries to the alternator. It nearly melted a near-by primary wire harness.
I listen close every time I click it, making sure I hear the same sound. If it ever sounded different, I would immediately investigate.
It looks like this.
