I've not told our insurance yet - I'll call hers tomorrow and if she's admitted liability then I won't bother with ours. You've got 48 hours to report it to your insurer.
I had a look at the clamping regs - a sign at the enterance of a car park (and no where else) is not acceptable, a sign where you cannot read the details is not acceptable (Vine vs Watham Forest), a clamper not displaying the company emblem on their vehicle is not acceptable (they were in an unmarked MPV). Clamper admitted to me that they had to put the sign high up and not where they should put it because the Wok bar employees kept ripping them down.
Let your insurance know now! Give them her details and leave them to chase her - also report it to the police immediatley - you should've had them at the scene if there were injuries.