I also consider it within the realm of possibility that the pin folks don't know they aren't supposed to use Gary Wolf characters. It's a big organization, after all.
But it's most likely that the remaining contract(s) stipulate merchandise is OK, but not rubberheads. Merch makes money, and Wolf would see some of that.
Jessica is gone from PI, but Roger lives on in Anaheim's toontown, so it's not like there is no working contract left around.