Aside from who you're backing and the fact you're using BTC, which I agree might make sense in a classic risk/reward scenario, you're also betting on the website still being there in 4 years, though, which might be the bet with the biggest odds !
That is definitely one of the greatest risks. In the cryptocurrency sector, very few of the gambling sites and exchanges have that much lifespan. So if you are making a bet, which will be decided only in 2024, there is a real chance that the website will go down before that and you will lose your coins. I have never made any bets, which makes me to wait for more than three months.