Aristocrat has not published a return-to-player percentage for Golden Gong in the specifications available. That matters because RTP is the long-run average return to players, not a target for any single session. Without a published figure, any specific percentage you see quoted online may be an estimate or a venue-specific setting rather than the game's fixed return.
What is published is the game's profile: high volatility, a 5x3 grid, 25 paylines, a minimum bet of A$0.01, and a jackpot feature. Volatility describes how returns are distributed. A high-volatility pokie tends to produce fewer wins, often smaller, but with the potential for larger payouts. It does not tell you what the average return is.