If DFW to MIA is on AA you will arrive at term D(Blue)
You will have to walk to term E(Yellow) for QR departure, term D s big may take 30 min total
At term E you will take a short train ride to satellite E.
You will remain airside throughout, no need to go through security
If you have time I would check out the FL/AC by D30
I've only been to the QR lounge once it was not impressive.
As always confirm departure gate at MIA

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