You do not have a warranty claim unless you fullfil the terms of Moblio Life which would probably be unique.
The car is more than eight years old which is going to make getting a goodwill contribution difficult to secure without resorting to legal violence.
I suggest that you get your files as complete as possible in terms of the full history of the car, make it clear to MB UK what you have by way of known history and make it clear that so far as you are concerned it is a matter of unacceptable corrosion to the point that the product was/is not fit for purpose.
You may have to threaten or take legal action but you will have an ''uphill struggle'' I suspect.
Do a search on this Forum.....lots of information about corrosion/rust issues.
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