You will get a letter from whatever company you work for asking why you didn’t do as you were asked by ATC. On that note, why didn’t you do as you were asked? If unhappy with the instruction given by ATC tell them your unable. This lets them plan around you and sort out the other traffic. Lots of big heavies in DXB, plus a lot of traffic so slowing up so early against ATC instruction can cause big problems for ATC and also the other aircraft.