GF - I do not have any inside information but as I recall there is no SSR coverage at low level in the Ballina area, only ADS-B. Hence:
A/ No only the A 320
B/ Not applicable
C/ I would think no
D/ The ENR controller would not have detected the Jab
E/ No because the system did not know about the Jab
F/ See E
More importantly, from the ATSB website, the Jab reported 4NM east of Lismore, which would make it 11NM west of Ballina, arguably not in the broadcast area of 10NM. (CASA - Now expanded to 15NM, always mopping up the last debacle; never looking for the next)
That should however have alerted the CA/GRO that the Jab was crossing the track of the A320, both on descent. In my view, that should have warranted a traffic alert to both aircraft.
But therein lies the rub, the A320 had already detected the Jab on TCAS, albeit without ALT information. (Jab ALT not selected), so detection was made, the A320 crew looked for but did not sight the Jab, so any involvement by the CA/GRO, at this stage, was superfluous
This Australia, is what CASA OAR thinks about paragraph 34 of the Airspace Policy Statement 2018 (AAPS) "34. The Government considers the safety of passenger transport services as the first priority in airspace administration and CASA should respond quickly to emerging changes in risk levels for passenger transport operations. ....." This is the airspace configuration chosen by CASA to operate Jetstar, Virgin and now Qantas jet operations into a rapidly expanding airport. Clearly there have been many "leading" safety indicators of separation issues at Ballina. (By leading, in this context, I mean when incidents occur that do not kill anybody, a lagging safety indicator is, therefore, one where deaths do occur.) How Jetstar's safety management system (SMS) does not classify operations at Ballina as an extreme risk, I cannot imagine. I know CASA does not have a functioning SMS so their inactivity does not surprise me. Perhaps Virgin and Qantas could apply their SMS and start kicking down doors at CASA.
Who else is there; Airservices and the ATSB? Airservices seems to have woken up to a deteriorating problem in the lower altitudes, they must be amazed that CASA OAR has done nothing. Class E to 1500 AGL, as proposed, would help but surveillance is required where needed and the US Class E rules are the only workable ones.
ATSB? Yes, I wrote to them a few months ago about the nonsensical arrangement at Sunshine Coast airport. There CASA requires a control tower because the airport falls within the Ministerial guidelines for Class D airspace (AAPS Table 1). CASA then allows Jetstar to operate outside of the Tower hours, presumably to save a few dollars of ATC costs. An Aero Commander (Incident AO-2019-62) took off at 6am using the into wind runway direction, only to find a Jetstar A320 turning on to final for a downwind landing; they just missed! ATSB claimed in the report that it was a simple matter of the pilots not communicating efficiently on the CTAF. In their response to me they said that if they saw any latent safety issues they would certainly act upon them. Well if an airline electing not to have the Tower on duty, no Class E airspace and not even a UNICOM operating constitutes no latent safety issues, then I came from another planet!