This was another of the dumb zombie jokes I came up with a while ago.
In addition to the dumb joke, there’s a grain of upcoming story arc information in this. George isn’t performing up to his old standards. That’s going to be a thing down the road.
Years ago for a role playing game I did the medical examiner’s symbol thing and never actually used it. When I was planning to add details to stuff for this strip I remembered it and added it to the back of the metal clipboard/paper work thingy that John has in panel three. It’s handy that I’m a digital hoarder sometimes.