Would you be able to download The Grounds file from somewhere? I know you said you've tried reinstalling it, but I feel like your map file might be broke in some way?
You might also want to simply manually uninstall it. Feral-Heart is fairly small I think, and I think it'd delete easily.
One last thing, there could be a permission problem. Feral-Heart tends to install itself in the Local Disk (C:), which is often set under different rules for editing rather than folders like documents, pictures, videos, etc. If you haven't set permissions to allow things to edit stuff in the Feral-Heart folder, it might not work.
Sorry if I've only told you things you've tried, but I hope you get it fixed.