A8 4.2 Bj 95 cooling water lossr

It's a very bad message.
After the evening return from a 500 km motorway drive, I found a pool of water at the front right under the car the next morning.
Cooling water loss about 0.5 liters filled up and driven to the workshop full of worry.No drop of water lost!!.
Only after 3 to 4 hours of cooling in the workshop could the fitters recognize the first drops.
The workshop had an A8 case like this before -with the following result:_
Seals renewed, but leaks again after 3 to 4 weeks. -cost EUR 400,
Finally, only the exchange of the whole unit was remedyed because apparently the seals do not fit the housing and therefore the leak is not to be corrected
Total costs then EUR 1500 .
Can it be?
Who has experience with it?
I have to decide soon what to do.
It appears that AUDI supplies inadequate replacement seals and thus triggers a cost avalanche for a lapalia.
Please share experiences and how you solved the problem.

Thank you

Welcome

Gerd