He has a point. With no definite 'cause' the ATSB have tossed the ball into CASA's court in regarding pilot medical and aircraft maintenance.
"We don't know, but we'll throw our mates at CASA a bone".
It doesn't matter if those things had any bearing at all, this bloke may have just fcuked up. The fact that he flouted the regs though is now part of a public investigation. More fuel for those at CASA who believe that pilots are simply criminals that haven't been caught yet...