Looking through the loop I couldn't find where
dtmDateOfBirth
is defined:
For Each objxmlEventPartyIDNode In aobjXmlInputDoc.DocumentElement.SelectNodes...
strPartyID = objxmlEventPartyIDNode.InnerText
objCaseParty.PartyId = strPartyID
objCaseParty.DateOfBirth = dtmDateOfBirth
i += 1
Next