[John W]

I had some changed 2 years ago, as well as one of the cams. The bike at that time was just on 3 years old, 24k service.

Ducati just weren't interested, despite me emailing and calling them a number of times. I posted copies of various threads about this to show it was a common fault, and even mentioned the number of generations this particular part has gone through. big fat nothing.
In the end I just paid the bill and moved on.

If you can get them to pay you will have done exceptionally well, but I would expect it to be a painful experience for you.