The problem is that legalities are more important than common sense.
"Why didn't CASA take action"? Is exactly the same question social workers get asked "Why didn't you remove that abused child from its drunken parent?"
The answer of course is that CASA, like the social worker, has to prepare a fully documented legal case, with every i dotted and t crossed, because the offended parent/aviator is going to let loose a lawyer shouting "Nazi Jackboot thugs!" , "denied natural justice!", "procedural fairness!", etc. etc.
If Mr. Hempel had successfully weathered "a hundred" rounds with CASA, I think it is unfair to blame CASA for perhaps being measured, thorough and perhaps slow in attempting to clip Mr. Hempels wings yet again.
Give CASA a break.