Drupal 7 aliases for a certain content type producing 404
Do you have any folder's in your root directory called "charities" or is there any rewrite rule in your.htaccess file? I know it's a long shot, but I had a very similar problem once and this turned out to be the cause. 

Also, try putting "?q=" before the alias when you type in the url and see if that works (e.g., http://yourdomain.com/?q=alias/path). it will point to problems related to my other suggestions.