I now believe that this story is a hoax.
Did you check with ATS?
They have the most ruthlessly thorough pile of ferrets I know of. Seems like I saw something about that a week or 3 ago on there—may have been the same thing you’ve been finding. Maybe not.
Seems to me there were some different features in the items on ATS about it. And, there were some ATSers from the region in Italy purportedly involved. IIRC.
I don’t recall any connection with Mt Etna at the time, though. IIRC, they were at a complete loss as to how to explain the clocks changing.
There may have been some speculations about cosmic rays; ray weapons experiments; time differential experiments or attacks or cosmic something or others . . . no one seemed to have any explanation that was satisfying.