Thank you for the request. To view the documents you should be added as a sub-user to the main GroupDocs account that Verizon SiteTraker use or the view/embed link for the document should contain "signature" property in the URL. This property can be added and generated via the GroupDocs SDK, for more info please check this documentation
Also you can check documentation
related to the document access rights.
All these should be made by the Verizon SiteTraker owners so please notify them with this info.