While this seems idiotic, how hard can it be to submit a copy of the death certificate?
Send the judge the video.
Certificates of Death are provided (at a cost ) by the funeral/crematory/interment company (here in the states, not sure about the aussies). For any legal process requiring a COD, an original is usually required.
Seems pretty straightforward, the youngun has been performing for a few years, and this should be taken care of by her representation.
Just damn......
KYPD