Why won't the app sending me scam notifications show up so I can uninstall it?

So I clicked "Allow notifications" on some sketchy link, and I got flooded with fake virus threat pop-ups. I managed to find where the notifications were coming from and turned them off, but now I want to actually remove the thing. The problem is it doesn't show up anywhere—not in my apps list, not in the Start menu, not in Add or Remove Programs. The only place I can find it is buried in the notification settings.

How do I locate and delete something that only appears in notification settings and nowhere else? Is there a way to trace where it's actually running from, or is it enough to just leave the notifications disabled? I'd rather get rid of it entirely than leave it sitting on the system.