That is a nice piece of hacking work. I'd lay 99.9% odds on that write-protect pin being left floating. (Which would mean he'll have to go through the same exercise again. He should have gone ahead and fixed it this time.)
+1 karma to LG for including that schematic. I will remember that little tidbit of information the next time I'm shopping for a TV.
Yeah, that blew me away. How often do you see schematics for ANYTHING anymore, much less a TV?
Most appliances still include a basic wiring diagram (helped me find a corroded connector in my fridge once), but the circuit boards are usually not diagrammed out.