So I have a client (this could only come from the government) who has a bunch of MS Word docs they want entered into a database, and short of manual entry, I feel like convertin
I looks like you have the wrong node name in your XPath expression. Replace all occurrences of w:document with w:wordDocument. So it should be:
w:document
w:wordDocument
XmlNodeList node = xmlDoc.SelectNodes("//w:wordDocument/descendant::w:t|//w:wordDocument/descendant::w:p|//w:wordDocument/descendant::w:tab", nsmgr);