Have you actually tried to use Youcam or any other webcam software or are you just presumming it doesn't work because it's not listed under sound manager?
You can search your Windows drive for "RAVCpl64.exe" and try to run it. This file has the File Description "Realtek HD Audio Manager" and is included in your Audio
drivers, whether it's installed for your particular hardware or not I don't know.
I would also consider contacting Fujitsu there maybe something we're missing or at least they should be able to tell you what the Aux device is and if the Realtek HD Audio Manager should be available. If you do contact them I would include a link to this thread.