Engine Rattling And Whining Sounds problems of the 2015 Audi S8

Was driving on a Saturday afternoon down a busy street when my car started sputtering and had very reduced power. I was able to eventually get to the side of the road and shut the car off. Tried starting the car after a resting period and car would not start. Let it sit longer and finally got it to start but car had very little power when pressing on the gas , but I was able to get to my local Audi dealer for a diagnosis. ($190. 00 + tax). I informed the technician of the issues I saw and also that I heard a whining noise coming from the engine. Diagnosis was that both turbos had significant "play" in them and they needed to be replaced. The tech said that this is caused by an oil screen deep inside the engine, which is a known cause of this issue. Price to repair would be $11,500. 00!!!! if this is a known issue as Audi states, why isn't this a recall issue, especially with the cost incurred by consumers?.