Edit: Sorry, I haven't noticed you said you already tried to restore it. But did you try to restore it through the Dreamhost admin panel or through the phpMyAdmin? It worked for me in the admin panel and I tried it several times.
Another option is to go to phpMyAdmin and if the database is still there, export the tables from there. Then create a new database and import the tables into it, that way you will recover all the information. If the old database still exists, you will have to use another name for the new database and change the DB name in config.php in WordPress.