Only admin can see bulk operations in view
You need to install the sub module in VBO called Actions Permissions.


  ACTIONS PERMISSIONS
  
  A module called actions_permissions is included in the package. This
  module generates a permission for each action, and VBO honors those
  permissions before showing or executing the corresponding actions.
  This is useful if you want to provide your VBO to several groups of
  users with different privileges: the same view will accommodate those
  different groups, showing to each the actions that they are permitted
  to see.


For your view make sure that you add the relationship to the flag



something like this (adjust as appropriate)



Afterwards navigate to the permissions screen, and enable Execute Flag (or unflag) a node for your roles



For your view of content you need to add the field Bulk Operations: Content (NOT bulk Operations:Flag').



And last but not least, make sure your flag permissions are set for your roles.