Yes, this is true. If the alarm / central locking is not working with a current key, a new key is unlikely to help. Any dealer should be able to program a key to the ECU to make the car start though.
The 'problem' if problem there is with cloning keys is that if you lose one, you cannot remove it from the system. So there's always a key out there that will start your car. Not a biggy in the grand scheme of things, though.
I would like a new key for my Ghibli but services here in terms of cloning seem rather less advanced than across the pond
C