Walk out back and look at the place where they wash the cars.
Now ask your self. Do these guys look like English is their first language ?
I don't speak spanish, but your sign might work better if it was.
This is the least of your problems at Irvine service.
They actually crashed my car (645i) when I left it with them.
Then blamed it on another unknown customer.
Didn't even apologize. Took 3 weeks to repair and wasn't ready to pick up when they told me to come get it.
I've since used Sterling, although they also washed my car without asking.
Perhaps All German Auto in Escondido is an alternative.
Rates are about 50 -75% of dealer cost.
You could sue in small claims for a professional polish to correct the paint.
About $400 around here. Not for the money, just the idea that they are so literally "careless"