Some key points:

1) The cars were MADE TO ORDER.

2) Two employees turned a blind eye to outrageous numbers.

3) Renault ***PROFITED*** from the abuse.

Look at it this way. You supply some goods to me. These goods happen to be below some agreed upon quality standard. However, I can still make a profit doing whatever it is that I'm doing with these goods. So, I don't say a thing, and allow you to continue selling me these sub-par goods. Then, some time later, I decide to turn around and sue you because you didn't supply goods of the quality we had agreed upon.

I agree that a lie is a lie, no matter how little that white lie may be. However, that's not the entire issue here.