When I connect a Microsoft Lifecam VX-3000 (I know it's ancient), it does not appear as a supported device in Cheese, let alone Skype.
However, when I run lsusb, it appears in the device list in the terminal.
Perhaps this post from 2010 could help?
https://burgerminds.wordpress.com/2010/03/15/microsoft-lifecam-vx-3000-and-gnulinux/