No, on both counts. I, for one, refuse to allow anyone to re-define our language to the point where "honor" and "cowardice" are compatible. They are not. Perspective and/or experience is irrelevant and that, frankly, is what has got us into all kinds of trouble. Allowing any group in our society to exit social norms and redifine our language to suit their own terms is outrageous. "Honor" and "respect" are easily found in the dictionary. Violence perpetrated and justified outside of these definintions is indicative of contemporary pathology, period.
Wanting to kill due perceived slight is bad enough, but the dueling described in the video has NOTHING in common with business conflict or "disrespect" felt by those who would ambush a defenseless adversary in a way the ensures their own safety, survival and escape. This is cowardice. Look at the video again and think about it.
Sumner was confronted by his adversary, one to one, and did not face lethal force projected from a safe distance. Surprised, he may have been. Many of his colleagues present were not. Not the same as a drive by, sorry.