The important point here is that files with the same file name are not overridden on extract. If that's the case, then you can monitor the root directory and the Directory Monitor will be smart enough to only open the 'new' log files. Note that Directory Monitors automatically monitor child directories.
So your Directory Monitor can monitor:
Zip 1 extracts to:
Later, zip 2 extracts to:
At this point, LogVIewPlus will have 5 files open.
Hope that helps. Please let me know if you have any further questions or issues.