Did you create the database walter21_city? It doesn't exist, which would explain a lot about why you can't import into it. The database itself needs to be created through cPanel in the same manner that MySQL databases do. Please create the database. Or is this supposed to be in walter21_cidade?
You should be able to import it through the PhpPgAdmin web interface. I doubt the cron would import it. If it won't import though, tell me the database you want that file imported into and I can import it from the command line for you.