Wrong Fuel Mercedes Sprinter

I’m on my way back from Maidstone services on the M20 to do a fuel drain on a Mercedes Sprinter who put 50 litres of the wrong fuel (unleaded) into a diesel. He told me the reason he did this was because he had set off that morning at 3am from Hounslow to go to Belgium to pick up some pharmaceutical items, he was unable to get back to the U.K on the euro tunnel due to problems so was diverted to the ferry at Callis but got there late and missed his ferry, had to wait a few hours until he could get another, he finally got back to the U.K at 11pm and noticed he was low on fuel but only had a shell fuel card so was hunting for shell petrol stations,when he found one it didn’t have any diesel so completely stressed out he just went into the next nearest fuel station and fuelled up, because he was tired and stressed he put the wrong fuel in, drove off up the road and broke down. He wasn’t having a very good because he had four different things go wrong for him that day…..to long to tell you all about. Needles to say he was back on the road in 30 mins and on his way home.