There have been many times that I couldn't find a new 3D layer because the camera had been moved & keyframed around the comp. Wish I knew this months ago and hopefully will save someone else some time.
Layer>Transform>Center in View
or right click layer>Transform>Center in View
Or Ctrl+Home
This will bring the layer in view of camera according to the CTI. It may still need adjusting, but a real time saver.