BA will not move you to gold if are short even in 1TP. I recommed that you do a fast MR out of DXB that earn you the required 5 TPs to get to gold.

You have many options to consider that are cheap: one of them is BA from AUH to MCT and back. Also I remember once I flew CX from DXB to BAH, however, I am not sure if that service still exist or not ?

Better to fly BA because the posting of the trip is faster and they will reset you account immediatly to zero and get your gold status. So if you have a return flight to LHR later it will be your first flight as a gold card holder and that trip will count for your future tier renewal qualification in Gold.