matthewgamm
You should know that use of Green Dot speed to expedite climb is only recommended below FL250. Above FL250 it is turbulence speed. Since you are already at turbulence speed you are not in a position to oblige the ATC. You have on your MCDU PERF page the ETA to the cleared level in time as well as the distance. So just say "Unable" and give that(ETAs) to ATC and let them do their job.