Website hacked. Code can't find database. PHP LOADER ERROR

That's a typical error message that occurs when the connection settings are incorrect. Are you able to verify your config/database.php file and make sure all the settings there are correct?

PS:
While I'm sure they host several websites with problematic code, I've encountered several instances where GoDaddy blames problems on 'code' when in reality it's something on their side. For them to say your website is hacked is a bigger issue though.

Codeigniter is simply one of the tools you need to learn to be a successful developer. Always add more tools to your coding arsenal!