Hey mate, sorry to hear but
some of the stuff sounds bullshit, i think he just wants extra stuff fixed while your paying
New bumper (just touching the surface)
New front bumper reinforcement (getting deeper.......)
Radiator Support panel (this is the piece the radiator, headlights, etc bolt onto...)
really need a decent effort to push that back
New engine cross member (lol need a F*CKING decent hit to screw one of these over)
but being his car
i think he has the right to choose the prefered repairer?
go to some smaller pannel beaters and get a cash quote
those are generally the cheapest because if they quote it like insurance work
all new parts etc your gonna end up paying bulk...