Here is a start.
There is a write-up of the incident here:
http://www.aviationheritage.org/oldn..._on_isuzu.html
It mentions specifically A6M3 “Hamps" attacking A72-81 and an "Irving" (Nakajima J1N) attacking one of the rescue PBY Catalinas. (Some write-ups mention two Irvings). Other attacking planes are described as "fighters".
No mention of units.
Another photo here:
https://www.awm.gov.au/collection/C290362