Car fax is not 100% accurate and it does not matter to them. They already got your money and if you read the small print on there website they do state they might not have all or any of the reports on the car your looking up! They are very behind in retrieving data i know i was burned by them, i bought a car that i thought had a clean history according to them, and it was not, and after many emails and calling the cooperate office, they never refunded my money! Not all wrecks etc. are reported and even if they are, some can take up to 4 years to show on the car fax reports! read this website: http://www.consumeraffairs.com/news04/2006/10/carfax_facts.html
Thanks for the heads up mate. you should report them to consumer advice board etc, see whether you can get your money back someway.