Views : Syntax error or access violation: 1142 (???)
Based on your comment, I see that each database only provides privileges to their respective user - and it seems implicit that you're using different users for each database.

That means that your Drupal MySQL user doesn't have access to the CiviCRM database.  For Views to work properly, the Drupal user must have permission to run SELECT statements on the CiviCRM database.  From the documentation you linked: "If you have different database users for your CiviCRM and Drupal databases, then you need to grant SELECT access for the Drupal user to all the CiviCRM tables."

Please try granting this access and try again, you should be good to go!