Enterprise won’t refund us over a car crash that wasn’t our fault

We paid €850 excess on the condition it would be reimbursed. A year later, we are no nearer to getting our money backIn July 2016 my partner and I rented a car from Enterprise in France. During our holiday we were hit from behind and the other driver signed a statement admitting he was responsible for the crash. When we returned the car Enterprise made us pay €850 (£780), which it promised to return after it had collected payment from the other driver’s insurer.
Last Novemb