I have golden skins unlocked for four of my characters (Nemo, Coco, Macchiato, Carrot). However, I am only able to see Nemo's golden skin in the character selection screen, the others just show their default skins. Changing skins and then changing back does not solve the issue. The only character of these that I have a non-default skin for besides the golden ones is Coco (the bath towel skin from the DLC), and that one displays without issue.