For reference, take a look at the same section from CDAR2_QRDAIII_DSTU_R1_2012NOV.pdf base standard document, pp39 says;

c. This legalAuthenticator SHALL contain exactly one [1..1] assignedEntity (CONF:19670).
i. This assignedEntity MAY contain zero or one [0..1] representedOrganization (CONF:19671).
1. The representedOrganization, if present, SHALL contain at least one [1..*] id (CONF:19672).
2. The representedOrganization, if present, SHOULD contain zero or one [0..1] name (CONF:19673).

In the CMS QRDA EP & HQR 2015 Implementation Guide, pp39;

c. This legalAuthenticator SHALL contain exactly one [1..1] assignedEntity (CONF:19670).
i. This assignedEntity MAY contain zero or one [0..1] representedOrganization (CONF:19671).
When the legalAuthenticator is a DSV, the representedOrganization/id is the DSV TIN.
1. The representedOrganization, if present, SHALL contain at least one [1..*] id (CONF:19671).
2. The representedOrganization, if present, SHOULD contain zero or one [0..1] name (CONF:19673).

The CONF: 19671 is being used twice here presumably by mistake. The second instance above probably should have retained the 19672 conformance number. The rule in the Lantana rules file (.sch) retains the 19672 conformance number as shown below;
<sch:assert id="a-77-19672" test="not(cda:legalAuthenticator/cda:assignedEntity/cda:representedOrganization) or cda:legalAuthenticator/cda:assignedEntity/cda:representedOrganization[count(cda:id) > 0]">The representedOrganization, if present, SHALL contain at least one [1..*] id (CONF:19672).</sch:assert>
Please correct the CMS QRDA EP & HQR 2015 Implementation Guide.
See attached JIRA Description Text for a formatted version, easier to read.