[ogden]

That's all lovely, but the simple fact is the blue car hit the grey one, not the red one, so the grey car claims from the red car. During the wrangling that follows, the red car may be found to be 100% liable, and the blue car 0%, but that's for the insurers to resolve between themselves.

All this "you weren't in the car, it's not your fault" is quite sweet, in a naive way, but doesn't reflect the reality of how the chain of claims will work.

Of course the right thing to do here is ask a solicitor, not a web forum.