Maybe it was not the poll worker who cast the ballot. There are plenty of gubmint employees who would know the names and addresses of the dearly departed. I would look inside the IRS and the Social Security Administration.
There are districts and precincts that regularly report way over 100% of the voters registered there voting. They vote Democrat, and it is not government workers or the like cheating. It’s just outright cheating at the source - poll workers and captains, etc. There are districts that report not ONE Republican vote....they are giddy in their power of the cheat.