rgonig2
To rule out the server incompatible, why don't you set up the osTicket locally and do the upgrade, then upload to live server?
Setup XAMPP or something similar: https://howtohelpdesk.com/install-xampp-on-windows-10/
Then setup osTicket, like you would in your server, and restore backup v1.10.4 and upgrade
If everything goes well then take a backup and upload to live server and restore the database