Is this a valid routing for an AONE3
 

DXB-LHR (stop)
LHR-YVR (overnight but less than 24 hours)
YVR-JFK (connection)
JFK-DCA (stop)
DCA-JFK (connection)
JFK-LAX (connection)
LAX-HKG (connection)
HKG-BKK (stop)
BKK-HKG (connection)
HKG-DXB

Other questions?
1. Can I booked AA7336 JFK-LAX operated by QF connecting at LAX to AA6119 LAX-HKG? I know it is valid for online connections only so I am wondering if booking AA to AA is okay where I would assume QF to CX is not?

2. My travel agent is the US (where I am based but will be in DXB this winter) has sent it to BA rates. She first tried CX but they said BA must do the pricing since they are the first over the water carrier. Will BA allow her to issue the ticket in the US using the published AED fare or will they use the minimum fare check and want me to pay the price for USA originations?

Thanks.

You have two transcons (yvr-jfk and jfk-lax) and it will be priced at US rates if issued in the US. To get UAE rates, you have to have it issued in the UAE or anywhere cheaper than the UAE.

Is only 1 trans-con permitted?

Correct, only 1 trans-con.

And why oh why would you waste 2 segments on JFK-DCA-JFK?