I have the entire tape and spent 18 months on an off and two weeks atthe time researching this.
First the Lithgow panther or any other panther in Australia are not Leopards. While there are remote possibilities that Leopards/cougars and other exotic big cats roam the Australian bush, only Victoria (where breeding populations of puma are fact (although black pumas are unheard of these days anywhere else) and Western Australia-where bronwish/tawny white cougars are fact) the black creatures seen elsewhere are not big cats but possibly a new species of Marsupial cat or a related species to the Thylacoleo carnifex-the Australian Marsupial Lion)
The below photograph shows how huge this other big black cat was.
It was black in the video but i have enhanced it to bring out details, the cat is pitch black.
I will post another shot of how it was in the video if anyone is interested.