Manually creating Security Key gives PHP error
Well then. Apparently my shell user was using a different version of php than my domain. I was still at 5.6 on my shell user. I was all sorts of confused because I had a phpinfo.php file setup at my domain showing PHP 7.0, and in the web hosting domain panel, I had 7.0 chosen. Finally wrote to support and they sent directions on how to change it. Once I updated that, the security key was created just fine.