Usually, commitment schemes are used for this: https://en.wikipedia.org/wiki/Commitment_scheme

(However, if the stakes are high enough, the party that learns the outcome first can choose to exit the protocol if they are unsatisfied with the result.)

I think mine from 2017 is a commitment scheme. Certainly is not unique or novel.

https://darkcephas.blogspot.com/2017/07/fair-random-number-g...

If you're worried about someone exiting the protocol, you can use a smart contract to lock their funds so that if they simply exit then they lose all their money.