Sounds like they want a USB based, VC system. How big is the room?

Usually we provide a thin client PC (to run whatever VC platform), bluetooth keyboard/mouse and then pair cameras and audio to suit for room size.

Larger rooms, take a look at Nureva, at least for the microphones. They can be speakers as well.

As for voice reinforcement, wireless mic with some sort of DSP is still your bet bet.

USB 3.0 is still a pain to extend without spending thousands. More and more products are 3.0 only and not backwards compatible, especially cameras. So if you're looking for easy USB extension with plenty of options, stick to 2.0 devices.