You need a witness who seen the incident and can say it was the lorry drivers fault 100%
You will need a statement, diagram/drawing and time line of events from your witness.
Other wise you may open a can of worms which was best to keep shut.
Been there done that and even though it was a blantant colision from a van driver all the way down the side of my Pug 306 my insurance company nearly paid the van driver out until I got my act together
