Coded UI Test: UnauthorizedAccessException when using networking API

I am trying to create Coded UI Tests for my Windows Phone 8.1 app, but are having some difficulties with my test methods.

In my test methods, I first invoke a method that connects with the API of my backend. The API call makes my backend send a notification to my app. What I want my UI test to do now, is test and verify that the UI is properly displaying the notification and data it received.

In short: I want to make a test which triggers a notification from my backend, and then verifies that the UI behaves as expected after receiving it.

The problem with this is that, whenever I call the method, which calls the backend API, I get an:

System.UnauthorizedAccessException: Use of networking APIs requires the ID_CAP_NETWORKING capability to be defined in the application manifest

This flag is properly set in the application manifest itself and for good reasons, I cannot set it in my Coded UI Test project, since it has no application manifest.

I tried working around this by making a third project with only the API (so that I have a phone, test and API project). The test-project would now invoke the API calling method in another project, but that did not help.

Are there any workarounds to this and if so, what would they be?

Thanks!