I'm using Magic Fields 2 plugin to create taxonomies and fields to display on the site. Your plugin looks like what I need to send an email with a reference number and post title in the subject.
Is your plugin compatible with MF2 at all? (in db, it is stored in table: (wpdb)_mf_custom_fields)
I'm calling data in my template with
<?php echo get('job_reference_number'); ?>