Yes - it is valid

For an extra USD150 you could also stopover in DFW

If you chose to drop AUS and also to fly ...ORD-PVG-HKG... then the itinerary would be below 22,000 miles and so be the less expensive xCIR22 instead of the more expensive xCIR26 - a saving of AUD1800 in business (though that would then be AA ORD-PVG instead of CX ORD-HKG)