TextureRenderer alternative

I want to include overhead cams of the heroes in my RTS. I looked up TestCameraMan and I got it working in a test of my own, but it doesn't work when integrated into the main application.

My main application uses two separate GameState objects, one for the actual game, and one for the GUI. When I pass the TextureRenderer JUST the player spatial to render, it renders fine. If I try to pass it the entire rootNode, which I wish to do because I need the land and scenery rendered as well, the entire quad and the entire Node that the quad is attached to completely disappear.

SO my question is: are there any alternatives to TextureRenderer, where I can add a camera to a scene and have it render to a quad?