Earlier in this thread, there were posts that believed the pilot, Blake Wilson, held a NZ CPL(H) but not an Australian equivalent. However the ATSB report makes it clear he had done his legwork and registered for an equivalent in Feb 23 which was granted in March 23. He wasn't employed by Nautilus ìn a ground support role until April the following year.
ATSB report mentions footage of final flight path captured on two security cameras, but their video summary seems to only show footage from one of these cameras (repeated a second time cropped in). While grainy, the helicopter still seems to have been upright when making final climb. If so, flipping inverted must have been quite rapid in final moments of flight.
Separately, the section of the report on "airside access and security" seems to leave at least one question open...