About crew rest
The first Airbus cockpit crew rest (A340-300) was two bunks accessed directly from the flight deck. It wasn't popular because there was no sitting area and it tended to be noisy.
On current A340s it normally occupies part of the bulk hold space, so a long way from the flight deck, but equipped with proper seats. I'm not sure if this is available on the A330-200. Maybe an AFR person can tell us.
The debris from AF447 with "crew rest" on it almost certainly indicates it's an LDMCR - lower deck mobile crew rest. This container-like module, primarily intended by Airbus to be for cabin crew rest, occupies the forwardmost position in the rear hold. Again, maybe someone from AFR can tell us whether this was being used as cockpit crew rest.