Shawn, rather than answer your question directly, I'd like help you understand some basic principles of Dynamo that I think will get you quite far. Most of the time, the name of an output that you connect to the input of another node will need to match. This isn't a universal rule, but in the top of your script you have elements. These are revit elements, look for a node that will help you extract the geometry from those elements, which in your case might match the geometry input on the DirectShape.ByGeometry.
The next input on the Direct Shape.By Geometry is category. What you have input are elements. It is looking for the name of a category. (the node is basically asking what category should this direct shape be? a wall, a floor, etc.)
See if that helps.