KevinTheJedi After the making the change to the Database Options section | Mysql Login info subsection of the ost-config.php file below, osTicket is now using the upgraded database MySQL database on the new port 3307:
define('DBHOST','localhost:3307');
As you explained, all that was needed was to add the :3307 after the hostname "localhost" ( define('DBHOST','localhost:3307');) and then restart IIS to make PHP reread the ost-config.php configuration file, and reconnect osTicket to the new database on the new port.
Admin Panel -->Dashboard --> Information now shows we are running MySQL DB v5.7.37. I tested opening, assigning, commenting, and closing tickets. Everything works as expected. Thanks!