From what I can gather the aircraft and personnel involved are probably from Marine Rotational Force-Darwin. Apart from a brief expression of sympathy by the SECDEF, US Defense/Navy/Marines official websites have noticeably silent on the subject I assume whilst relatives are inforrmed and the facts verified. Also to minimize the potential effect on the relatives of other members of individual units should the relevant units be identified..
MV-22Bs from MRF-D have recently been operating with HMASs Adelaide and Canberra. The USS America ARG with the 31 MEU embarked were involved in the recently concluded Exercise Malabar 2023 off the East Coast.
My thoughts also with those involved and their families, Semper Fi.