Rotation Issues

Your uploaded screenshot tells us nothing about your comp or your workflow except that you have three 3D layers selected, and you are not looking at one of the custom cameras. 

If you are trying to rotate the whole group as one layer, then parent all three layers to a 3D null that is at the center of rotation and rotate the null.

If all three layers share the same plane (all have the same Z axis), and you want them to rotate independently180º so they are all lined up, use a simple pick whipt expression to tie the rotation of the two outside layers to the middle layer. 

If you want something else, please explain your design goals in detail and embed a screenshot of the whole UI by simply copying and paste, or dragging the screenshot to the reply field instead of uploading it with the Drag & drop here or browse to attach button so you can see the screenshot in your post.