I think this is wrong tbh. Double Elim. finals aren't really bo3 in sets, its just 2 separate sets. And since only one set was played i think it makes sense to use the map results from the one set as the overall result. The 2x bo3 set finals exists because in a Double Elimination bracket everyone deserves to come back from one loss, even in the final. But the person coming from the loser bracket has already lost once at that point.

I think you are confusing this with the other form of handling Double Elim. finals which is 1 set bo5 with a 1 map advantage to the guy coming from the winner bracket. Not the same thing imho.