That discoloration is not good. Have you taken it to any hand car washes at all? I ask as some of them use products which aren't designed to be used for cleaning cars. If you've not then I'd be taking it to Audi for them to look at.
Regarding the camera cleaning, have you topped up the tank for the nozzle. If so too much solution may have been used. I had a similar issue with my washer jets and I'd put in too much solution and not diluted it enough.