I have another quick question. Can WiFi Guard app detect all devices that connect via Wi-Fi, whether it be on a isolated or non-isolated SSID? The computer I'm running it on isn't the PC connected to the router and is behind a simple switch. The app does detect all wired devices that connect to the network.
It really depends on whether your router isolates WiFi (and wired) networks from each other. If it does, then devices from one network cannot see devices in another network, and WiFi Guard will not be able to detect them.
This isolation can usually be configured in the router settings. So if you want to be able to detect devices everywhere, the isolation needs to be turned off.