erictch
Did you check your System Logs for any Mail Fetcher errors? You can also find an email that "wasn't fetched" by osTicket, view the raw email, copy the full Message ID, go to the database, go to the _thread_entry_email table, and do a search for where mid = '<message_id_here>'
. If you find a record then the email did in-fact get fetched by osTicket you just don't see it for whatever reason (department access, etc.). If you can't find it then it definitely was not fetched. If it's not fetched then you should have some sort of logs that tell you why (in osTicket system logs, PHP error logs, Apache error logs, etc.).
Cheers.