why not just execute it as shell command (using PHP CLI)?
<?php exec('php my-other-script.php > /dev/null 2>/dev/null &'); ?>
code untested; taken from SO and modified to fit your needs :)
I use https://pushover.net/ across the system - basically anything I want to be immediately notified of (new user, new event, new blog post, code pushed to production server, etc...) sends me and the admins a notification - easy enough to add it to php.