This is a painting of a four legged animal with a large head and muzzle looking like a Thylacoleo carnifex (marsupial lion) but with the front legs and paws similar to those of a Thylacine (Tasmanian tiger). [Permissions TBD]
Compare this paining with the one from the Northern Kimberleys (8) also thought to be of a marsupial lion.
Rock paintings were sometimes painted over and many layers of paint are found on this particular painting. Perhaps after the marsupial lion became extinct and this image was painted over, the image was ‘updated’ with characteristics more similar to a Thylacine (Tasmanian tiger). This animal used to live in mainland Australia until 3,000/4,000 years ago.
Reference: Taçon, Paul S.C. and Steve Webb. 2017. Art and megafauna in the Top End of the Northern Territory, Australia: Illusion or reality? Web: https://press-files.anu.edu.au/downloads/press/n3991/pdf/ch08.pdf