Help with the oil stop cable…

Hola SLKler, I recently bought a SLK 200 compressor R170. At a car dealer who is also a car master. By chance I became aware of the keyword oil top kabal. So, now I passed by at MB, and let me see if the oil top cable is already in it and they told me that it can be installed for 50,- EUR. Unfortunately, it was found that the oil is already in the control unit and also the Lambda probe would be affected. Since this is actually still In the warranty of the dealer, the oil stop cable has not been installed with the hint, both the camshaft adjuster, as well as the wire harness, the control unit and the lampda probe should be replaced (approx. 3000 EUR). *uaaa* In case of demand with the seller (Car dealer/master) he said that he wants to clean this and then install the oil stop cable (MB wants to earn only money). Now my question is, is that right, or what can be cleaned and what needs to be replaced? According to another MB branch, in which I asked for a second opinion, only the oil lubrication is a damage or lack of the thing, even without the engine or the control unit ticking around. The OBD lamp is not yet burning. They continued to think that at least the wire harness and the magnet at the camshaft adjuster should be replaced, about 350 + 60 EUR. My legal protection could be Unfortunately I don’t say if it’s a lack, for that I would have to consult a lawyer, which I would like to do without, especially since my other car is already sold, I have bought new rims, winter tires etc., i.e. I don’t want to actually resign from the dealer. Well, what do you think, is it a lack if it has not yet come to a damage to the ECU, Lambda probe etc.? I am grateful for every tip, maybe someone has already had such a thing done and knows the prices with work time, because I can’t do it myself 😉