@axiom00

I did a bit more research and determined that XCP-ng was passing the USB device through to the guest OS, although either didn't have the right drivers for my z-wave USB stick, or otherwise didn't know what to do with it; so it always just passed it to the guest as a root hub.

I wasn't particularly interested in spending too much more time on it so I purchased the following PCI-E card and passed the whole controller through to the guest. That solved my problem and it has been working ever since.

https://www.amazon.com/gp/product/B00JFR2H64/ref=ppx_yo_dt_b_asin_title_o05_s00

@axiom00

I did a bit more research and determined that XCP-ng was passing the USB device through to the guest OS, although either didn't have the right drivers for my z-wave USB stick, or otherwise didn't know what to do with it; so it always just passed it to the guest as a root hub.

I wasn't particularly interested in spending too much more time on it so I purchased the following PCI-E card and passed the whole controller through to the guest. That solved my problem and it has been working ever since.

https://www.amazon.com/gp/product/B00JFR2H64/ref=ppx_yo_dt_b_asin_title_o05_s00

First, I want to say thanks to @fjen, @redalert11, and @FrCo for providing this information. It has certainly gotten me closer to USB pass through with a Linux VM.

@FrCo or @redalert11: were either of you able to get your AEOTEC Z-wave 5 gen USB to show as a device in your guest VM?

I followed the instructions above and was able to configure USB Pass through in XCP-ng Center, however in my CentOS 7.6 guest VM I only ever see the following devices:

[root@centos7.6 ~]$ lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 002: ID 0627:0001 Adomax Technology Co., Ltd 
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

I also checked dmesg and didn't find a single trace that it attempted to load the usb device.