It’s very possible that the 20k includes a whole lot of other fees. When looking at estimates to ship our two small dogs back to Aus from the Middle East, the flight itself forms only a small part of the cost.

As an example, the rabies test that they must have min. 180 days before export is going to cost approx ~1000AUD per dog. Then there are other tests, paperwork, vet fees, stamps, and the cost of the 10 day quarantine in Australia (plus all of the paperwork, vet fees, stamps etc that are required again on the Australian end as well).

edited to add: domestic animals can’t enter Australia as excess luggage, they must be manifest cargo, which adds substantially to the cost.