I uploaded my save file into Google drive where you can download it, open the file and replace your current saves with these.
You can reach game save by going C:\Users\"computer name here"\Documents\My Games
Back up your save if you wish to keep them and turn off Cloud sync if issues occur.

Download Link[drive.google.com]

After that, open the island mode, click on continue, and talk with everyone on the beach. After that, the achievement should pop for you.

Thank you for visiting my guide. I created this guide because I only completed this achievement after a year because it takes a while and you have to replay it several times to get the achievement and I got too lazy to do that and stopped playing. So I hope I've helped you not to have to spend time in a boring mode (in my opinion lol).