I followed your instructions to extract the msu which was successful and then attempted to install the extracted cab.  Received the message below:

C:\Users\Administrator>dism.exe /online /add-package /packagepath:C:\KB-Hotfix\W
indows6.1-KB2685813-x64.cab

Deployment Image Servicing and Management tool
Version: 6.1.7601.24499

Image Version: 6.1.7601.24499

Error: 87

The add-package option is unknown.
For more information, refer to the help by running DISM.exe /?.

The DISM log file can be found at C:\Windows\Logs\DISM\dism.log