If the aircraft is in charter category CASA requires it to carry $1M per passenger in liability. Have a look at the maintenance release, it'll tell you if the plane is in charter category - then you will know that (if the owner/operator has done the right thing) the plane has that level of cover. There is no requirement for any cover for the pilot.
Certainly, if another pilot crashed my plane and was found to be at fault, I would expect them to pay the excess. (again 1% - 2% of hull value).
Occasionally I get a pilot with less than the precribed number of total hours required by my insurance company wanting to fly the plane. I get them indivually listed on the policy as "insured". The insurance company stipulate that if the plane is damaged while they are flying, the excess is doubled. I make sure that these pilots are aware of this fact before they fly the plane.
I'm happy to show any (potential) customer a copy of my certificate of insurance.