Spotlight does not show all the network interfaces.
How does Spotlight get information about the available network interfaces?
The product uses the following WMI query to get information about available network interfaces:
wmic path Win32_PerfRawData_Tcpip_NetworkInterface get name
Run it in command prompt on the monitored machine where Spotlight shows no the adapter and see if missing card is in the list.
If the adapter does not appear on the result then the problem might be adapter and not with Spotlight.