Lowly turboprop driver here.
On any type I have come across yet, fuel usage on ground has been a function only of engine power over time. Nothing else. Taxi speed, distance etc. seem to have only a minuscule or no effect at all, and seeing that OAT, pressure, wind etc. are a given when on the ground and cannot be influenced, IŽd disregard their influence as well.
So the option to just sit somewhere out of the way, with the parking brake set and therefore not even having to ask the question whether the brakes will be abnormally heated or not, and increase engine power a little bit to a prudent value seems to have much merit. Also, if not already in use, starting the APU might speed up the desired reduction of fuel on board.
IŽd therefore respectfully suggest asking ATC to hold in a quiet taxiway, the runway bypass or something like this (airfield dependent), obtain the approval to increase power to a setting e. g. for a crossbleed start, and just wait there until the MTOW is achieved.
If allowed in the company and not already done, is the use of alternate passenger weights an option?
Here is another accident that was caused by taxiing around while riding the brakes: a Swissair Caravelle that was taxied up and down the runway with high power settings in order to clear the fog, then took off and suffered a fire in the main wheel bay.