Should a driver, employed as part of their normal work, to look after children in the community, and drive these children in their own car for work -pay all the excess if a child (client ) being transported in that car causes damage to the owner/staff car and an others vehicle.

Driving recently a car for work-2 years at this job. Using my own private car -doing regular work for welfare agency /brokerage.
I am transporting children for NSW Community Services .

A group of 4 including (3 children and myself) are getting into the car .

A child of 7 1/2 -the oldest , seats himself in the front of the car and spontaneously releases the handbrake .

I was about to put the other children in the car .

The child is in the car alone. I notice the car is moving and run around to the front /driver side, to try and pull handbrake before momentum builds.

The car is stopped by hitting the car parked 2 meters ahead.

I send in my incident/accident report . My company is vague and evasive -about their own policy on this matter -then after a few days of my phoning , they say they do not contribute or pay insurance -*I likely have to pay at fault excess of $600-they say it's the nature of the job -that's why they want driver to have comprehensive.

I comment I was not told this before - and due to often driving people with disability , challenging behaviour and children regularly for them - I now have to decide to not transport people as this is too expensive, and dangerous , and is unfair to the car owners/staff-to have to pay full costs and be at fault.

I will note that doing this job- 1 staff to 3 children is increasingly common- it's ironic that welfare agencies are more and more over burdening staff with clients including children it seems to save them and community services money -putting clients and staff in danger-in danger of being sued also -when in cars and out in the community.

... they say they do not contribute or pay insurance -*I likely have to pay at fault excess of $600-they say it's the nature of the job -that's why they want driver to have comprehensive.
...

And do you have comprehensive? I assume you do not.

In most states, parents are strictly liable, to a certain amount, for the negligent or intentional actions of their children. I see that you are in New South Wales, Australia. I woud check to see if such parental liability is also in effect there. A 7 1/2 year old child releasing the handbrake would probably bring such liability, on the part of the parents, into play. I suggest that you demand that they pay you your damages.

And the company could be liable for failing to properly notify you that, as an employee, your car is not insured even when used on company business.

I am puzzled, a bit, as to how this accident happened. Most cars now days have automatic transmission. Wasn't it in park? If so, the hand brake shouldn't have been necessary. Did it slip into gear somehow? Or was it manual transmission, in neutral, and rolled when the brake was released?

First, ANY question on law needs to include your general locale as laws vary by area.

AK asks some key questions here that we need answers to. Can the agency produce documentation that indicates you were required to have coverage?