I haven't had to show my Emerald cards at the HKG lounges for the past 3 years, they go by the status shown on the boarding pass and in the computer (unlike BA lounges which believe the physical card and not the computer or BP). Your routing is fine, but could be optimized quite a bit to increase the earned mileage. In D all segments earn on QFF quite nicely, though I doubt it is enough miles for a couple of free J tickets to the US (more like 1 J award).

I you wanted to maximize your mileage earn, you could do DTW-ORD-MIA-LAX/LAS-DFW-SJU-JFK-HKG (you get the idea). Adding a LHR-DXB-LHR loop costs a day (you have a 2 hour turnaround at Dubai, never leave the airport) but earns lots of miles and SCs.