One of my plugins broke when I tried to update it, how do I safely uninstall it?

I recently tried to update Yoast SEO to its most recent release (4.3). My site is running the most recent version of WordPress (4.7.2).

When I tried to install it, it gave me some error having to do with files, and I can't find the error message anymore. Yoast ceased to be displayed as a plugin installed on the server (not listed under active or inactive either). I tried to re-install it, but it threw an error along the lines of

error: tried to create a directory that already exists

or something like that.

So, here's my question:

How do I uninstall Yoast when it doesn't show up as installed anymore? Is it safe to do so?(if I need to use FTP, what file path might I find it at?)

Thanks for any help! If I didn't provide enough information, please let me know what I need to give (I'm sort of new at WordPress)