fatal error on WPEngine Hosting

You are using a PHP version lower than 5.4. As stated in the description this plugin needs at least PHP 5.4 to run.

Please have a try using this plugin with a newer version of PHP and review your rating afterwards.

Can’t, it’s on managed hosting, I don’t control the PHP version. I’ll revise to a 3 until a version exists that can be used on a common hosting company like WPEngine.

Please have a look at https://wpengine.com/blog/php-5-5-upgrade-available-wp-engine-customers/. You can already run this plugin on WPEngine, you just need to upgrade to PHP > 5.4.