We can trade cites all day long I’m sure. But official investigations have determined that the evidence of there being POWs still in Vietnam after the war was flimsey at best and much of it based on unfounded refugee testimony with no evidence nor backing, often because they thought it would get them into the US. I know in one instance a refugee’s claim was investigated and it was determined the white military men he reported seeing were in fact Soviet advisors, not Americans.
Publ. 1997 <><><>< Available on Amazon Books
There is much info on the Net also, as there is about any of the policies that have been systematically fracturing every area of our nation along with her culture.