I read a different article that said during the excavation of a known grave many years ago, the excavators may have slightly over-dug into Yardley’s grave and found the skull but didn’t excavate further. The Yardley grave itself is right in front of the alter of the original church in the center of the aisle, so a very prominent placing, whoever the person may have been.
It might have been a Venerated Relic................