Forgotten Hollow not playable

@polkapyr I can def duplicate this on your save so the save does look pretty corrupt. I don't think there's a way to fix it.

Did you ever make any backups ? Did you test all the automatic backups the game makes ?

https://sims4.crinrict.com/eng/2014/09/save-games/#wiederherstellen

Have you ever used any custom worlds ? What mods have you been using ?

EDIT: Found a solution but this will make you loose everything from the Vampire pack you currently have on your save. So you need to do a few steps first

1. Create a backup of your save for safekeeping
2. Go into the save and save every family/house that uses something from the Vamp pack to your library or at least make a list of what you need to add back/change later
3. Trash the GP04 folder again or just disable it: https://sims4.crinrict.com/eng/2017/03/disable-single-packs/
4. Load the game. Forgotton Hallow will be greyed out
5. Save the file (use save as). This will remove ALL Vampire content from the save game.
6. Exit the game. Enable/Reinstall the pack
7. Start the save you saved without the pack installed
8. Forgotten Hallo should now look like it did when you first installed that pack.
9. Now you can put stuff back from the library if you had to save any houses. For Sims, check what happened to them if they were Vamps before. If they were removed or just stripped of their Vampirism. If they were just stripped, you can make them vamps again. If not, replace them from the Sims you backed up.
10. If you're happy, you can delete all backups you made of the corrupted save.