Apple replaced the camera free of charge (and a 2 hour wait). And all is well.
Today I just came across an article at iDropNews that says Apple is now openly acknowledging that some iPhone 6 Plus devices have a faulty rear camera and has announced a recall. If you are experiencing a rear camera that will not focus, click the following link to find out if your Serial Number is eligible for free replacement: iSight Camera Replacement
According to Apple, defective units were sold between September 2014 and January 2015.