Why didn't an Audi dealer spot dangerous problems with my 2006 A4?

I own a 2006 Audi A4. I have paid £670 to have a service and cambelt change. I suspected the car’s brakes were in need of some attention so was surprised that the service report stated nothing was required. I felt I couldn't accept this report without a second opinion so took the car for a “Free Brake Check” at a local garage. The findings were shocking. All four brakes needed urgent attention. Pads were worn to below 1mm on the rear wheels. Discs were below manufacturers limits on the front wheels. Also, the offside rear suspension spring was broken. They classed the car as being in urgent need of repair. I have strong doubts that any of the work I paid for has been done at all. I don't think the Audi dealer has put a spanner to this car. They also allowed me to drive off in a dangerous car without informing me at all. Audi is aware and I awaiting a response. In the meantime any advice would be appreciated.
I wasn’t sure if the faults had been missed by the Audi dealer or the independent offering the “free check” had found some profitable work to be done on the car. But EN later wrote back to tell us:

“On the strength of your original reply I sent a message to Audi UK via the 'contact us' link on their website. I then had a call from the Audi dealer who said he was really embarrassed and deeply sorry to hear of the faults with my car. I agreed to let them re-inspect my car, providing I could witness this. Audi agreed that the brakes needed replacing and that the rear suspension spring was broken. They also agreed there were serious issues at the centre that needed sorting to prevent it happening again. In short I had a full refund and all the work identified by “free check” was agreed and was to be done by Audi, free of charge. In addition I was loaned a top of the range A6 3.0TDI auto as a courtesy car, which I am reluctantly returning to them tomorrow. So all in all it worked out OK for me. Thank you again.”
Answered by Honest John on

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