Yeah, this is certainly going to throw a wrench into the works.

A fairly simplistic option for a scoring system: Oracles make a prediction for all four characters involved in each match, with each of the four predictions worth up to 12.50 points (12.50 x 4 = traditional max score of 50 points per match).

Example:

Oracle contestant predicts A with 40%, B with 30%, C with 20%, and D with 10%
Match turns out A with 35%, B with 30%, C with 30%, and D with 5%

A = 12.5 - (40-35) = 7.5 points
B = 12.5 - (30-30) = 12.5 points
C = 12.5 - (30-20) = 2.5 points
D = 12.5 - (10-5) = 7.5 points

Grand total: 30 points

I'm not sure how a penalty for incorrect winners would factor into that kind of system, though I suppose people could get negativescores if they missed by more than 12.50%...but this kind of system may be harsh enough as it is.