You'll have to bear with me, I'm not very familiar with indexhibit. You did indeed set up a new database correctly on our end. Taking a look at their installation directions, you'll need to go here next: www.yourdomain.com/ndxzstudio/install.php (I've verified this works with your domain). You should be able to continue the installation there, following the steps outlined here:
If you still run into trouble connecting it with the database, from taking a brief look at your installation, you may need to check out the file located at /yourdomain.com/ndxsite/config/config.example.php. You'd edit it using the information from the MySQL Databases page in your DreamHost web panel, pertaining to the new blank database you just created there. Once you've filled in those blanks, re-save the file as config.php. That shouldn't be necessary though, as it sounds like going through the rest of the installation process on your site will create that file for you.
If you have any questions, let me know, and I'll try to help!