Just try it yourself. Every QVD contains a header in XML, filled with all sorts of interesting details. One of the tags in this header is <CreatorDoc> which specifies the name of the document that last created this QVD. The XML header can be read into a QVW with an appropriate LOAD statement. Or if it's just a single shot, open your QVD in Notepad++ or any other text editor that isn't afraid of large files, and jump straight to the end.
You could try the Governance Dashboard which does all of that for you. However, this dashboard is targetting larger environments and may prove a bit costly to set-up and use for one source document only.