Thanks for the reply.  I marked up a couple of pics.  I circled the damaged area, and pointed the transition.  The Mature bark IS the color of the damage.  But new bark on a 4ft whip is yellow/green ish.  It really girdled the entire middle section.  And eventually I cut it off, below the Arrow.  I am thinking something like a Canker, but I can't find any references of that in this tree.  

The suckers and an adventitious bud below the cut are growing well, so I think I can rule out "Culture/ Watering".  It was a 2-3 gallon Bare root, I could see the rootball size.  I DID contact the nursery, and am on the list for a replacement in the fall.  

I'm concerned mostly, about the future.  I spent many years enjoying these trees in the Japanese Garden at the Missouri Botanical garden, and finally have the space for some.  Propagation and even doing a mass planting at some point has been pondered.  But they are not cheap, and if there is something Local to me, that is causing this, I need to re-think.  I Should have brought the diseased area to someone, but I thought, Hmm, carry possibly infectious plant bits to a Nursery, might not be welcomed.  

Thanks for all the help, hopefully these pics can give a better idea.