Not found "Create Add new " option in the Current Employer field if the org name typing
From the documentation:


  If you want to force the user to submit only a value from the list (or
  leave to leave it blank), thereby preventing the user from creating
  new organization records, set the require_match config option to TRUE
  (it defaults to FALSE):

global $civicrm_setting;
$civicrm_setting['eu.tttp.publicautocomplete']['require_match'] = TRUE;



This means, if you want to allow the user to create new organization records, you would omit this line, or set it to FALSE.

Also note: If you omit the line or set it to FALSE, you won't actually see a "Create New" option; you'll just be able to type in the name of an organization that's not in the list of options.

EDIT:

Regarding the potential for typos and duplicates, that will always exist any time you allow the user to enter a new organization name. CiviCRM will  follow the unattended dedupe rule for organizations when deciding whether to use an existing org or create a new one.