WP Cron single event schedule issue

I’ve been having issues where I schedule a post but its cron job is never set. I’ve been using Cron Gui as well as _get_cron_array() to check what is being stored in the option. Our install has 100,000+pageviews/day. We also have up to 10 admins/editors who could be changing content on the site at any given time. I’ve been testing by updating the post_date with the quick edit tool in edit.php. I’ve been logging the results of _get_cron_array() on line 1411 in wp-admin\includes\ajax-actions.php

I could not figure out how to hack this and get the option to set correctly. My only guess is that perhaps multiple processes are over-writing the option (cron in wp_options). Our storage engine is myism. We have had talks of switching to inodb.

I wrote an event query to clean up missed-schedule posts but I would like to know if anyone has been able to resolve this issue.