I'm using a skin modifier to create a straight line between two vertices, to simulate a cord being stretched between two moveable points.
I'm following the suggestion in this response Rig a rope spanning two objects (minus using soft bodies, since my cord doesn't need to have curves).
The cord shows up in editing and even in Rendered Mode for viewport shading, but it's not in my final renders. I have 'Use modifier for render' set to true for all four modifiers for this line (the anchor hook, the moveable hook, the skin, and the subsurf) but I'm not sure what else I need to set to make this show up in the actual render.

(I'm also new to blender so I'm guessing I'm missing something obvious, but I haven't found any other questions on this)