Instead of upvoting system for rewards, maybe having people straight up gamble their Hive for it and have it stored on an escrow account. Organizer gets a cut in the winning side's portion for standard fees. Incentives for those that want to start a prediction would include having more % of the reward cut if there's good participation turn out.
If there's a 2nd layer token on Hive Engine, the incentives can be tokens that give owners a cut from the transaction fees in the market.