One thing that might speak against it being the result of a power use is that Cao seems like kind of an odd target. He was more trusted than D1, but I don't think he was at the top of anyone's townreads (though he did have a claimed power, which I guess they might have wanted to get rid of). Though I suppose it might be a targetable power (like, maybe BW has something like "the first time you're about to be busted, a random person voting you is busted instead" or something like that), in which case it could make sense.
And thanks for the explanation about the numbers, it does seem to make sense (even if it's an odd coincidence that the person seven steps away from the intended target ended up dying).
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The above should obviously read "it might
not be a targetable power".
Also, the forum seems to be feeling bad again, as I took me roughly five weeks to make this post.