Seeing which outcomes stay out of reach
The 6x5 grid and the 96.50% RTP describe the game, not its timing. How often the bonus round comes is not known in advance. The result of one session stays random whatever the RTP, so two players with the same bet can finish far apart after the same number of spins.
96.49% and 96.50% are the two RTP versions of this game. Which version runs on a given site is shown only in the game rules, so check there before you rely on any figure. The RTP is the long-run return on A$100 staked, and it says nothing about a single session.
x15,000 is the most this game pays, measured against the bet. At the highest bet allowed here, A$125, that ceiling comes to A$1,875,000. The ceiling is reached very rarely, so plan any session around your own limits rather than around that figure.