Do you tow with it or has it got a tow bar fitted that vauxhall can see.?
If they won't replace it I would take it to a garage you can trust and get the clutch out. If you have worn it down it will be easy to see. If the clutch has broken up then show it to vauxhall.
I think they will replace it with only that mileage on it but if you want them to do it and you pay ask to see it when it is all stripped down and show you what is worn.
Is the clutch slipping?
If they won't replace it I would take it to a garage you can trust and get the clutch out. If you have worn it down it will be easy to see. If the clutch has broken up then show it to vauxhall.
I think they will replace it with only that mileage on it but if you want them to do it and you pay ask to see it when it is all stripped down and show you what is worn.
Is the clutch slipping?