Using XSLT to read CCD values into an Extension Custom class

We have a source that sends a ConfidentialEncounter indicator in the CCD, but only as a section narrative(not a coded entry).  They have shared the template and CCD examples  . We added the ConfidentialEncounter property in the Encounter Extension  class and created a ConfidentialEncounter.xsl file , which includes the Encounters.xsl and placed it in the Custom/Import/Section-Modules folder . The xsl file appears to correctly read in the ConfidentialEncounter value from the CCD. The problem is that this value is not getting saved in the Encounter.Extension.ConfidentialEncounter property. 

I have reviewed the documentation. There is mention of how to populate extension properties but it mentions the Entry-Module , not the Section-Module. Any ideas on how to make the extension value land in the Encounter property of the SDA container? 

Thank you for reading.

PS: WRC was not helpful. They said it is supported but do not know how it is accomplished