Well, I suppose evidence for the trickier (B) would be if the inexplicable EMF signal also had information telling the widow exactly where to dig in order to retrieve her late husband's buried treasure, or it clearly predicted future events, etc.

That would be in contrast to weird measurements that can't be explained with current science... Buuuut it's a sine-wave that only occur when the neighbors are running their microwave oven. A physicist might get an interesting paper out of it, but it wouldn't upend our understanding of life and death.