Mercedes might have covered the damage under warranty if the fault was down to poor manufacturing – and the previous owner could prove this – but what's more likely is that the wheel hit a pothole and it was this that caused the crack. Unfortunately, low profile tyres and the large wheels they're attached to are prone to this sort of damage. You could try and get the Jaguar dealer to pay up, but again, I'm not sure how you would prove the damage was already there and not caused by you hitting a pothole.

I'd write a letter to the dealer you bought the car from – explain the issue, the evidence you have that it was a poor repair and argue that the damage should have been picked up before the car was sold. If the car was described as being in "excellent condition" (or words similar) this will also help your case. Repairing a wheel shouldn't cost much for a dealer so that might stand you in good stead, although I think your best hope might be a goodwill gesture.