Sorry for the long winded reply,
Which breaker tripped off, you can eliminate a lot of trouble shooting if you can eliminate 3 circuits. Witch ever one was off you need to start working your way back from the phone charger to the outlet(If that was the circuit), outlet wiring then wire to breaker. The lowest amp breaker still needs over an 1800 watt draw before it will trip that is a lot of power. I would keep everything off until you fined the issue, a bed fire is no joke. I keep all breakers and inverter off unless needed.
You will also fined a 12VDC fuse box under the back seat, you can probe with a test light to see if any of the fuses are blown. or pull them one at a time and see if there is a black burnt spot in the window. The fan may have shorted out prier to full self destruction, and or a ground fault in one of the taped wires. Same process as the breaker, if you fined a blown fuse, look up what it supply's and start working from the outlet or appliance back to the fuse. I have found several aftermarket wires chafed through and shorted to ground.
I agree with MountainBikeRomer, use DC power for everything you can, TV, laptop, fans, and phones, your wasting as much as 50% power efficiency when inverting to AC then back to DC. This is more relevant when running off battery but still good practice.
Please keep us updated on your progress.
2007 E350 RB50 Sportsmoble, Always longwinded and misspelled.