You would be replacing this line
$spec.deviceChange[0].device.backing.deviceName = "path:2/0/7 version:2"
That value contains the actual path, which you don't know since the USB device was possibly moved.
To specify the USB device without knowing the actual path, you use the VID and the PID in that pattern.
That way the ESXi will look for that specific USB device.
The only problem is when you have 2 or more identical USB devices connected.
I don't know what ESXi will do in that case. Perhaps select the 1st one it encounters ?
Btw the explanation of such a pattern is specified at the top of the VirtualUSBUSBBackingInfo object description in the SDK.