Have completed it twice in the last werk won it both times but the outline is not gold or showing as complete what’s the story with this one anyone else have the same problem
Had the same problem but every other finale is fine. Stuck at 69/70 Exhibitions because of it. 
It took me 3 races to win it, but once I did, it turned gold and I got the little trophy symbol on it.
Im not 100%sure but i think you have to win against either expert or unbeatable drivatars on that one.
UPDATE: I created my own route at Gauntlet and won it and got the gold today. 