No mechanism exists to launch it.
Attached to this post is a VI that has exactly the same front panel as the Edit Events dialog from LabVIEW 2017. You could put code behind it if you wanted to use it elsewhere, but the only thing currently on the block diagram is a bunch of FP terminals.
Edit Events Dialog.vi
OK turns out I was looking in the wrong place!
You have to browse to just System (Not System.Net.Networkinformation) and there it is..
Also the .net API browser courtesy of Microsoft comes in handy https://docs.microsoft.com/en-gb/dotnet/api/system.net.networkinformation.networkinterface.getisnetworkavailable?view=netframework-4.7.1#System_Net_NetworkInformation_NetworkInterface_GetIsNetworkAvailable