I have to say that after reading the OP's info and doing a bit of research into the fires mentioned I find it absolutely inconceivable that the fires were unrelated.

That's like London burning down, and on the exact same night Birmingham burning down too.... completely by coincidence.

Something obviously went on here that is beyond a few forest fires joining together.

I'd say that, all things considered, the electric comet theory is a lot more plausible than the alternatives.