Fortunately I live in a country (the Netherlands) where suing everybody is not yet common practise.

As a human factors engineer I do have some comments regarding the original posts.

Always make clear why repairs are necessary.
For a mechanic it is obvious that a broken timing belt usually damages an engine, for a average driver it is not. Most people have no idea what a timing belt is. If the final decision is left to the customer they should be made aware of the consequences. Especially when there are no noticeable symptoms.
It is like going to a home physician who recommends a visit to a cardiologist. If you have no noticeable cardiac problems it is likely you will say “I feel fine, I can still run a marathon” and if your busy you may wait 6 months. If however he says “you have a dilated artery and will drop dead next month” you will make that appointment the same day.

For the damage by coolant loss Mercedes is partly to blame. In this age of electronics it is strange that drivers should interpret gauges to prevent engine damage. At high speed or in busy traffic you can not look at a the temperature every second. With coolant loss the temp will go up and then return to normal values, the sensor is on top of the engine and steam without pressure is not very hot. That leaves only the low coolant light, not a very clear indicator of immediate total engine failure.
French cars have a big light that says “STOP” in addition there is a vocal command to stop. Most car manufactures seem not to like indications that their product may fail.