P1 takes and immediately uses Bad Omen P2 takes turn with 2 fewer dice P3 takes turn with 2 fewer dice, takes Good Omen P3 immediately takes a new turn with all dice (as per this thread), and claims the Queen
Bad Omen says that it can't be used during the final roll-off. We decided to play it as follows:
P4 is no longer under the effect of Bad Omen, takes final roll-off roll with all dice.
P1 still gets the extra die from Bad Omen, as not having it available would have been a severe disadvantage.