I have a bit of the same issue as this : QEMU/KVM/Virt-Manager: Passthrough of USB Webcam to Windows 7 Enterprise creates "NEC USB HUB", one-two year(s) later.
I tried 2 cameras for a security setup (because ispy doesn't works on Linux and there is no free good alternative including google drive auto-upload on a secured server that I know), none of them were seen by windows.
It happens that
lsusb returns 6 unknown hubs - which I don't know how to remove, as said Kevin Chen a bit less than 1 year ago -, pretty newbie in the VM world, and just not that aware in the Linux/Ubuntu use.
Nor do I know of course how to switch to USB 2.0 if it somehow possible (Cables are on USB 2.0 physical ports though if it was what he meant)
So, if anyone can light me up for a solution, I would be very grateful!