Use RhinoDoc.CreateHeadless without an open Rhino Document

I’m trying to create some unit tests for a Rhino Plugin.
I’ve tried running the following without Rhino open.

RhinoDoc doc2 = Rhino.RhinoDoc.CreateHeadless(null);

But when I do I get lots of errors, such as 'Unable to load DLL ‘rhcommon_c’ or ‘BadImageFormat’ amongst others. However when I run this exact code inside of Grasshopper it runs perfectly.
Does this code only work when run inside of a Rhino Instance?

All I need for my tests to work is a Rhino Object, but I do not believe I can get one of these without a document.


– Dale