That's true, but the reason people started refering to it as "lutz" on those Jabos was because what antique marble collectors called "lutz" had not been seen on a machine-made marble before. That's all. As you pointed out, in the experimental Jabo runs, green aventurine was called green aventurine, blue aventurine was called blue aventurine, and mica was called mica. When lutz appeared -- as they hoped it would -- people said OMG, lutz! Period.
It was believed to be the first time lutz had appeared on a machine made until a well-known and well-respected collector said, "Not really, I have some Alleys with lutz." And by golly he did. Marbles and pictures were shown around, and a small group of people started combing back through their Alleys and keeping an eye out for it. And a few more Alleys with lutz have since turned up.
That's all there is to it. Say lutz, and people know what you mean, as you say. It's just a convenience word. Others can argue about how that thing called lutz was produced, and when, and where, until the cows come home, but it doesn't make any difference.
No need to cast it in the light of the World-Wide Jabo Conspiracy some folks here seem to believe in . . .