Before your first spin on the reels
96.00% RTP describes the long run, not a single session, and it does not say when the bonus round comes. How often the bonus round appears is not known in advance. Each session is random, so the result of one session can land well above or well below the RTP, whatever the version running. Nobody can predict that outcome before the first spin.
96.00% is the only RTP the game lists for Vampy Party. Which RTP version is running is shown only in the game rules, so open the rules screen before the first spin. Vampy Party has one version, so there is no second option to weigh.
x5,000 is the maximum win of Vampy Party, a multiple of the bet, not a fixed sum. It is a ceiling that is reached very rarely. In money, the same multiple reads A$50,000 at the A$10 top example bet, and it grows as the bet grows.