Think I got scammed.

So i'm almost done with the story I killed the Kahn and I just have to confront Shimura but I'm on PS4, so when I bought the director's cut from the PlayStation store and when I hovered over the island of iki in the map it said "Upgrade to the ghost of tsushima director's cut for PS5 console by purchasing it from the PlayStation store" I don't have a PS5 and I've read other reddit posts saying that there's supposed to be a quest giver somewhere on the island of tsushima but can't find it on the map. I've also explored and liberated the bottom and middle half of tsushima but no quests or question marks anywhere. Is the director's cut full of shit and just ate up my money? OR do I have to completely 100% the main story before some kind of quest giver or something will show up for me to access Iki? OR do I have to do the upgrade to the PS5 thing? OR do I have to start a completely new game for me to access the island of iki? Someone help, I'm tempted to get a refund.