[euhlmann]

CameraServer.getInstance(), as the name implies, returns a singleton instance of CameraServer. That means server1 and server2 are the same in your code.

Here's how you might get both camera feeds into a single frame

// init
USBCamera cam0 = new USBCamera("cam0");
USBCamera cam1 = new USBCamera("cam1");
Image cam0Image = NIVision.imaqCreateImage(ImageType.IMAGE_RGB, 0);
Image cam1Image = NIVision.imaqCreateImage(ImageType.IMAGE_RGB, 0);
Image combinedImage = NIVision.imaqCreateImage(ImageType.IMAGE_RGB, 0);

cam0.openCamera();
cam1.openCamera();
cam0.startCapture();
cam1.startCapture();

// on each iteration
cam0.getImage(cam0Image);
cam1.getImage(cam1Image);
GetImageSizeResult cam0Size = NIVision.imaqGetImageSize(cam0Image);
GetImageSizeResult cam1Size = NIVision.imaqGetImageSize(cam1Image);
NIVision.imaqCopyRect(combinedImage, cam0Image, new Rect(0, 0, cam0Size.width, cam0Size.height), new Point(0, 0));
NIVision.imaqCopyRect(combinedImage, cam1Image, new Rect(0, 0, cam1Size.width, cam1Size.height), new Point(cam0Size.width, 0));

CameraServer.getInstance().setImage(combinedImage);

Disclaimer: untested, but you get the idea