These are different unlock codes... The one that's being brute forces is the "everyday" unlock code that enables certain power user and debugging features.

The rumored "unlock code" for when tivo goes tits-up is one that lets it function in "Boat Anchor Mode" without nagging the user endlessly that they should subscribe to the service. Now, if this is really a code that exists today or something that would be put into the doomsday software release is a question that hasn't been ansewered. Of course, if tivo goes under, all the tivo hackers will create some sort of guide data replacement in short order.

Matthew