The scuttle around the F/A-18 community is that everything on the aircraft is allegedly ok and they could not find a definitive reason for the engine 'shutdown'. The various OEMs are pointing at each other and the investigation is/was barely moving forward. The recent leverage applied by the US Navy looks to have helped and things are apparently moving, but no rumours have leaked as to the cause.
All rumour of course.
Not true. There is a cause suspected (known) but nothing will be published until 100% of the investigation is complete. The very public nature of the accident requires us to have all bases covered.