Problem solved! Thank you for the help!
I'd considered using that class but using exec() is so easy 😉 .. Here's a very stripped down version of what I did incase anyone else wants to do this sometime~
<?
$root_path = dirname(__FILE__);
$upload_dir = '/upload/';
$file = '1v1_Ruso_vs_Jor.mgx';
$filename = basename($file, '.mgx');
exec('zip -r ' . $root_path . $upload_dir . $filename . '.zip ' . $root_path . $upload_dir . $filename . '.mgx');
exec('rm ' . $root_path . $upload_dir . $file . ' -f');
?>