Is this extra to a normal service? If so it won’t get a stamp in the book (or has it been ticked as done in the history?).
The previous owner probably decided that as he was selling it he wouldn’t bother spending the extra £280.00
+1. Pretty much the same as body work inspections, brake fluid, coolant and air conditioning. Many people who only the car whilst it is under warranty skimp on these including fleet managers knowing it will be someone else’s problem once they’ve sold it on.
which makes me question the value of a “full main dealer service history”!!
The dealer can’t insist on the extra’s being done at service, that is down to the owner. Knowing the vehicle you want and what service items needed doing at specific time and/or mileage then you can ask if the work has been done and then negotiate on missing service items.