From memory, the Co-Pilot refused to speak to CASA: (legal advice?).
Also, I believe that she refused to attend the "Rural and Regional Affairs Reference's Committee" PEL AIR talkfest leaving the committee no option other than to subponea her which they 'declined' to do.
Which means, of course, that the Senate concluded an investigation and reached conclusions and recommendations re an aviation accident without interviewing both surviving pilots.
I think this is the first time a pilot has NOT been interviewed after such an event!
Couple that with the CVR and it should be enlightening when we hear from the ATSB. Mind you, the retrieval of the CVR is an ATSB responsibility (not CASA) and the boxes should have been recovered and transcribed/interpreted before the Senate set off on its merry way.
The Senate PEL AIR report is generally dismissed as 'politics' by most commentators overseas with whom I have spoken.
Mind you, you will go a long way to find anyone who has either actually read the report or considers the Senate's efforts as anything worthy of other than dismissal.
We will see.