It has to do with whether the carrier is permitted to pick up traffic...which I doubt CX is for a variety of reasons. The best way to check is with the galileo tool floating about. If it shows up in Galileo then usually its fine, if not then no. Given that it is purely a domestic flight, I seriously doubt it because few governments allow that much freedom for foreign carriers. I think the only routes that is allowed in the OW network are within Peru on Lan Chile/Peru, on Comair in various countries, and the LAX-JFK route on Qantas.