Good question.
The Hogan Group is apparently only “40 kilometres (25 mi) southeast of Wilsons Promontory” and Hogan Island “has a maximum elevation of 116 metres”.
One of the higher points on Wilsons Promontory appears to be Mt Oberon at 558m, which appears to be 60km from Hogan Island.
This would appear to make the island visible, even given the curvature of the Earth, but probably only on a very clear day. (But somebody might need to check the math & distances.)
Addendum: