Hi Glenn,
I am a qualified ISO 9001, ICAO and CASA auditor so I hope this helps. IMO opinion CASA does not have a safety management system and from my experience a very immature quality management system.
Once again, IMO, CASA could easily, in order to put you out of business, or whatever they did do (it is important to be very accurate about that), prove that you and/or your operation was a sufficient risk to air safety by providing a risk matrix.
As described in this simple you tube segment <https://www.youtube.com/watch?v=MrowycTmRXo> this is a consequence versus frequency matrix, used all over the world, to assess risk.It (a risk assessment policy) was adopted by the Commonwealth in 2014 and a simple guide to implementation can be seen on the ANAO website <https://www.anao.gov.au/work/corporate/anao-risk-management-policy-and-framework-2019-21>
To put you out of business would require you to be beyond management (i.e. medium - high risk) and in the extreme risk range - in other words the consequence of your actions are catastrophic and would happen with high frequency (see video)
These matrices are derived through peer input (Hazard Identification - HAZID), and easily reverse engineered, so it is very important that there is a representative spread of people making the decisions. That would require, as well as CASA staff, independent safety auditors, pilots/staff from businesses that you might have had an effect on and other independent/ not involved pilots/businesses. This means that if a risk matix can be supplied it is important to obtain the minutes of the hazard identification meeting to identify who was there and what they decided.
Finally, even if the risk matrix indicated that you personally, or your operation, was an extreme risk, the hazards should be recorded and should be subject to a risk mitigation exercise, (Hazard Analysis- HAZAN) to ascertain whether controls could be put in place to reduce the risk to what is known as, As Low As Reasonably Practicable (ALARP). If they could, a first step would have been to impose such controls and then re-audit in six months, and so on...
With this approach, not only could CASA show yourself, and the ombudsman, that you were a risk to the flying public, but that you were also beyond redemption, so their only choice was to shut you down.
I expect that no such document will be forthcoming, so what evidence do they have to prove they followed the Commonwealth's risk assessment guidelines in coming to their decision?
Once again, I hope this helps and the best of luck!