Just thought I would close the loop on this.
I did end up contacting PCGS
and having them correct the error, more out of curiosity than anything. A couple notes on the process:
-contacting them by phone was incredibly irritating and took over a week. The process is you call and put your number in the queue for a call back that day. If you don't call first thing in the morning, they will be full up for the day. If you miss the call back, or are on another call, you have to try again the next day.
-they had me send pictures
-they emailed back a week later or so indicating that yes, it was an error on their part and they would correct it
-they emailed me a FedEx label and had me submit the slab with an order form marked "mechanical error"
-I received the corrected slab back this past weekend, just under three months later
-the slab has the same cert number and the same grade but is now "gold shield," which I guess is some kind of a slight upgrade
Anyway - long process but in the end it didn't cost me anything and they corrected the error