Rental car infringement and towing away cost.

My sister and I rented a vehicle for a four-day trip in New Zealand. On the second day of our trip, I was stopped by police for speeding and my driver's licence was suspended. The police officer then contacted the rental company and informed them of the situation.
Following this, the rental company immediately terminated our rental agreement and arranged for the vehicle to be towed away. We were subsequently charged over $1,000 for the towing and related costs.
At the time, I explained to the rental company that my sister was an authorised driver and was fully licensed to continue driving the vehicle. I made it clear that I would not be driving the car any further. Despite this, the rental company refused to consider allowing my sister to continue the rental and insisted on terminating the agreement.
As a result, my sister and I were left stranded in a small town with all of our luggage and no access to alternative rental vehicles. We were forced to make our own arrangements to reach the next major town.
To add to this, the rental company later advised that the fuel tank was not full when the vehicle was returned and sought to charge us for the missing fuel and an administration fee. After I explained that we were not given any opportunity to refuel the vehicle because it had been taken from us unexpectedly, the administration fee was waived. However, the company still intends to charge us for the fuel.

Is this legally allowed? The towing costs appear unreasonable, as my sister could have driven the vehicle to the nearest branch or agreed drop-off location.
We should not be charged for fuel that we were prevented from replenishing because the vehicle was removed from our possession without notice.
We should not be charged for the remaining rental period (approximately $300) after the company chose to terminate the agreement and take back the vehicle. Also me and my sister are both on our restricted license.