I think it's a simple fix for you. One thing I notice in Cpanel is that the MySQL setup is a little bit misleading. It asks you for a username, but the actual username is "yourcpaneluser_yourmysqluser" ... same thing for the database. If you call your database "database" during Cpanel's MySQL setup, it actually calls the database "yourcpaneluser_database".

So even though you might have set up the username tvhorse, you actually need to use "cpaneluser_tvhorse" and same for your actual database, needs to be "cpaneluser_databasename". And replace "cpaneluser" with your actual cpanel username and don't use the quote marks. So if you make those changes in your config.php file, it should work.

Hope that helps.