Generally speaking I don't like reports being issued before all the facts are established but in this case they'd taken all the helicopters out of service in case it was a repeat of the previous problem.
this led to major disruption of the industry and the lives of people offshore & their families
They were able to establish that it was unlikely to be a mechanical problem - and no-one would believe any statement by the manufacturers, the service companies, the field operators, the unions or even the police - the AIB are the only ones who people trust so a very limited statement seems to be a reasonable thing to do in these circumstances