Hello Methe Crain,
It sounds that in your case the most straight-forward solution would be to change the settings in your app (if that is possible) and let FIddlerCore listen for changes but without attaching it. Attaching means setting the system proxy settings to 127.0.0.1:8888 and all applications that are using the system proxy will effectively start using Fiddler as a proxy.
In your case, you could use the startup settings (base example):
var startupSettings = new FiddlerCoreStartupSettingsBuilder()
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