Un-installing a submission that has been removed.

I installed a submission, unfortunately it was broken though.
I didn’t un-install it at first because it wasn’t really doing anything.

With the latest update, it breaks the game, really bad, a lot of things aren’t working.
It’s been removed from the workshop, when I try and un-install it I can’t remove it because it’s not showing up in my “installed” panel. It’s still installed though.

Can’t find anywhere to delete it though, besides the addon folder, but I don’t want to delete everything.