You have to finish the race.

But last week was rather strange as everybody had chrome skins except Trendf and I still got the trophy anyway,we ran another race [when Trendf changed skins] just to make sure the others got it.

Best bet if you aren't on the list for this Sunday is to be online and replace someone who just got the trophy,it's only one more race and everybody is there anyway,you would have to already be on KIGO1987 friends list,worth a try.