Just throwing this out there, but maybe somewhere along you assign to the camera location a reference to the labels location vector, and they are now referencing the same vector object. That's my only idea right now.
Glad you found it! Bugs like that are not always easy to spot.
You where right!
Instead of
public void lookAt(final Vector3f point) {
Callable<Void> exe = new Callable<Void>() {
public Void call() {
focus = point;
I should do:
public void lookAt(final Vector3f point){
Callable<Void> exe = new Callable<Void>() {
public Void call() {
focus.set(point);
Sorry I bothered you with such a trivial bug :|