Check the rules for your RTP version
Choose your bet size before the first spin, knowing that the bonus round comes at random. Nobody can tell in advance how often it lands, and the result of one session stays random whatever the RTP. The RTP only describes the average return over a very large number of spins, not what happens in the session in front of you.
Open the game rules before you bet to find which RTP version Miamiclub runs. That detail appears only in the game rules, so check there before you rely on any RTP figure. Four versions exist, and the rules name the one this game runs.
Set your bet with the maximum win in mind before any spin. The top prize is x25,000 of your bet, and the game reaches that ceiling very rarely. Treat the ceiling as a limit on the game, not as a result you should expect or chase.