I didn’t use the Blender camera in game - I deleted the camera from all my Blender models I converted to j3o binaries. The camera I used in the game was, as you mentioned, the camera that comes with the JME SimpleApplication class. The only point in production that I used the Blender camera was to render into sprites some of the images I used in the GUI, for example the image of a suitcase.
If you’re asking because you’re looking for a way to turn a Blender camera into a camera used in game, here’s a tip. In Blender, use a dummy object (i.e. a cube, cone, sphere…) and place it in the scene where you want the game camera. Then, in code, find the object, and place the camera in the same position as the dummy object.
Spatial cameraDummy = scene.getChild("CameraDummyObject");
Just remember to assign a material to your object or it won’t import properly.