Maybe there’s a misunderstanding (I don’t use simBrief regulary). SimBrief is not the problem, that’s correct. But simBrief didn’t calculate 9700 lbs as needed fuel for the trip itself, did it? If so, simBrief would actually be the problem. SimBrief calculates also reserve fuel, alternate fuel, extra fuel, taxi fuel, etc. As any decent planning tool would do. This is your 9700 lbs of fuel. You shouldn’t arrive empty at your destination. Actually using 2200 lbs on such a short trip isn’t that far off though.