PCGS Damage Or Mint Error?

I recently purchased several proof 2010 Lincoln pennies in PCGS Lyndall Bass-signed slabs to give away as gifts. One of the slabs looks like this:




The label is not aligned correctly and the penny has a spot at the top of Lincoln's head where some copper is missing and the Zinc alloy is visible. There is a small piece of copper in the middle of the spot and also some discoloration around the spot. Here's a close-up of the spot:






What are the chances that this is a mint error instead of PCGS damage? It's not clear to me how PCGS could have damaged the coin, but since they didn't get the label aligned correctly I wonder. Also, PCGS did not note the damage on the label, although since these were mass-produced Lyndall Bass signed slabs PCGS was probably working too quickly to notice. Based on the seller, I'm confident this is genuine PCGS.

Any suggestions about what I should do with it? I see four options: (1) return it to the seller for a replacement, (2) return it to PCGS under their guarantee, (3) hold on to it to show people that PCGS sometimes makes mistakes that are released into the wild, or (4) add it to my collection as an error (if it is truly an error). I welcome any other ideas.

--K