Right way up :
I would argue you don't. .
Unfortunately that is what the book says .
My responsibilities as a Commander dictate I ensure sufficient terrain clearance. If a controller makes a mistake (like we all can all do sometimes), I cannot just sit there and suck it up
Of course you will not suck it up. Common sense should always prevails if/when someones makes a mistake . My point was than in normal ops when receiving a vector , responsibility with terrain clearance move to ATC. That what we have been taught, and that is how people are expected to react and that is most probably the reason why the vector was not challenged by the EVA crew.