Arhh well...
So the insurance company is making you pay the excess to chase up the party at fault???
Usually your car would be repaired with no cost to you and then the people at fault would be contacted to fit the bill???
Thats how RACQ did my claim when i was hit from behind in my old skyline... The party who hit me said im sorry its my fault at the scene and then 4 days later said what are you talking about, you reversed into me... RACQ took care of it all and i never had to pay a cent...