Ended up being basically the same. The one 'trick' was that you cannot use the Navigate methods on the WebView2 but need to set the Source property
_webView.Source = new Uri(authorizeUri);
The WebView2 needs to initialize, and getting the initialization methods to work was giving my fits. But setting Source will also call the initialization methods in the background. Much better look
Thanks for the help @dotMorten_esri
Thanks,
-Joe