Maybe, I haven't been following the story close enough? I understood from previous comments the Ombudsman had acknowledged improper practice by CASA but failed to take any positive or rectification action?
Regardless of the independence of the Ombudsman, I suspect it would be a very game Ombudsman to make a finding of serious malfeasance or malpractice by CASA, it's Board or it's Minister.
The two you dropped out "...Senate Inquiries, various Coroners..." have made findings critical of CASA.