Well, I think in the case of the plates, you can make the case that it doesn't matter that you can't prove a negative because the probability is so low.

Which suggests that "you can't prove a negative" is the sort of thing that should be answered with "true, but sometimes it doesn't matter, and I don't think it matters this time."

I mean, I can't *prove* that M&Ms don't cause tornadoes, but I shouldn't have to.