new key (keyfob) - can a used one be reprogrammed?

[iampivot]

I need a new key/keyfob for my 2013 passat. I've seen conflicting information wether a used key (for an identical car) from a wrecker can be reprogrammed for my car or not. Does anyone know anything about this for the most recent 2012/2013 model cars?

Edit: From Immobilizer IV Key Matching - Ross-Tech Wiki; "Prerequisites: All keys are either new or were adapted to this car (IMMO-ID) before."

I assume this would mean that the key is adapter for the vehicle from the factory? Is re-adaptation possible?

Also found this; VW Key remote fob FAQ for mk4: disassembly for battery change, program instructions, and replacement cost

"if the car has immobilizer 2 you can reprogram used immobilizer chips (and used keys). If your car has immo 3 or above, you can't. A new key blade half is required since the immobilizer chip is inside that half. Again, you could use a used remote half if it's the same FCC ID or as parts."

Since the Passat B7 has immobilizer 4D, it looks like it won't accept a used key (the rfid chip part of it).