Crontab's are failing when they are created by becoming the AD user with 'sudo su - <accountname>' or as root using 'su - <accountname>'
Aug 5 09:09:01 Hostname crond: Permission denied
Aug 5 09:09:01 Hostname crond: CRON (username) ERROR: failed to open PAM security session: Success
Aug 5 09:09:01 Hostname crond: CRON (username) ERROR: cannot set security context
These errors are typically a result of the account that creates the crontab not having normal access to the system to the system. Privileged users can become other users without restriction so the crontab can be created. When the crontab needs to be run the user account is denied access.
Provide access to the machine through the users.allow file so the crontab can be successfully run or create the crontab using a different account.