I think that there is some truth in the article but a lot of bull. Firstly the fuel line is a return system not unlike a petrol engined car so yes when the fuel pump is energised the fuel will make a round trip to the engine and any excess back to the tank. As far as bits of metal getting into the engine and wrecking the internals this is pure fantasy as any particles would have to pass first through the fuel filter then gauze filter in each injector nozzle and then through the tiny holes in the end of each injector. IMO should the worst happen and you do not continue to run the car for any distance all that should be required is a tank drain, replace the high pressure fuel pump, have the injectors ultrasonically cleaned, new filter and reprime the system. Anyone daft enough to pay £7000 for this please come and see me I will take your money.
Having said all that BMW wanted £2500 to replace the blown turbo on my 320D. I source the turbo myself and it was fitted by an aftermarket BMW specialist for half the cost. £102 per hour plus vat is a rip off.