Just received confirmation from the solicitor that settlement has finally been made.
For some reason my insurers never received payment and put it in hands of a solicitor, this was last March. It went to court, we won and a CCJ was issued against the lorry driver. By this time costs had risen to over 7k. Now it's been paid.
The entire episode was somewhat odd. I can only assume that his insurer must have dumped him early on.