But again there's the problem that this info appears in the pilot, in which Hotch also assumes that the people in the Seattle field office will remember him "after busting my butt in this office for three years".

Only... At this point he's been in the BAU for (at least) almost six years, according to Gideon in 'A Real Rain'. Possibly people stay in the same field offices for a long time , but assuming everyone there remembers his three years there after at least six years?

I'm not sure I'd trust most of the non-essential info from the pilot.