thats a shoddy response from a company associated with such a valuable asset, and I only agree with what others said. Its a Merc problem, B&O have washed their hands of it.
its disappointing to see that despite the huge premium it takes to obtain a car such as the SLS, it still has its problems. for a car of that value, id expect perfection, and I would imagine you do as well.
however, having read your threads from the past, your a man of means and persuasion - im sure you will reach a satisfactory outcome!