Officially the CCR card is only valid for entry at LHR and JFK, no other locations are included.
The latest staff lounge access guide (was shown it in SIN) has the wording:
The Concorde Room Card does not grant entry into any other lounge (or lounge area) even though there may be a reference to Concorde Dining or Concorde Bar (for example at BOS, IAD, DXB & SIN)