It looks like someone ran into the back of him (see the crunched tail) and possible ran him off the road. Poor guy might not have had a chance. LIke "What the...Oh Nooooooo!"
Nope - I am afraid he lost the back end all on his own and hit a bollard at speed! If you look at the top of the bank, there seems to be a gap in the metal fence (pic 4?) - this wasn't there before he ploughed the fence backwards.....
....the car lost momentum as it spun round as it went down the embankment, hence the absence of damage to the front of the car. The car also narrowly missed the return conductor wire (suspended in the air) which also carries 25KV!!
It was lucky as a train traveling on the adjacent line noticed the car and managed to contact the signaler in time - the train you see in the picture was traveling in the OPPOSITE direction (at 110 mph), and TOWARDS the obstruction, but managed to stop in time.....
Cost?
Well if you add up the cost to the emergency services attending, damage to the railway infrastructure, delay to trains on the day etc, it comes to over a £500,000....... (or a million $ of anybodies money!!!)