I am not one, but would suggest that in order to get a conviction, it would have to be proved that they went back to DXB intending not to return to be interviewed.
Equally IANAL either! But as far as Emirates itself is concerned, if they impeded the investigation (recklessly?) by repatriating the crew, then they're in the frame.
For the crew, probably not an issue unless they declined to be interviewed by ATSB.
But at the end of the day, as others have suggested, probably less of a legal issue and more about not getting up the nose of ATSB or CASA - because that ain't a good thing
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