I can comment to the extent that I can confirm there are 6k/day consultants, and most of the ones I know aren't doing the kind of work where their 1-2 weeks of work generates 1-3% uplift on sales --- which is the kind of work Patrick did, and which a moment of thought will confirm for you pays for an extremely high consulting rate.
6k/day is high; quite high. But it's not implausible.
6k/day is high; quite high. But it's not implausible.