I spoke too soon. No go. After modifying the template, then logging in to the MFD and updating its templates, I attempted to scan a document. It asked for authentication. The key portion of the template looks like this (username and password fields scribbled to protect the guilty):
[service xrx_svc_file]
file_1{
* enum_filingpolicy DocumentFilingPolicy = NEW_AUTO_GENERATE;
* string RepositoryAlias = "Doc.IT";
* string DocumentPath = "My_Path";
string UserNetworkFilingLoginName = "OCR_account";
string UserNetworkFilingLoginID = "OCR_account_password";
enum_filingprotocol FilingProtocol = SMB;
string RepositoryName = "OCR-server:445";
string RepositoryVolume = "UserFolders";
string NDSTree = "";
string NDSNameContext = "";
boolean ServerValidationReq = FALSE;
enum_loginsource LoginSource = SYSTEM;
boolean DocumentDirectoryXSM = TRUE;
ref_invocation OutputDocument = xrx_document:doc_1;
}(XRX_STATUS_COMPLETED)
end