I do leatherwork. There is no "test" for leather.
You said it was confirmed as "genuine" leather. This term actually often is used for composite materials made of scrap leather fibers. In other words, facke leather. And yes, it smells like leather.
Later you say it is leather. That can be perceived as a contradiction of the first statement.
Did he actually use the term "genuine" leather, and if he did, did you ask him what that meant?
The International Union of Leather Technicians and Chemists has developed standards and tests for leather. It would involve a sample being taken and that sample would be destroyed. It would be expensive, and no cobbler has the capability to perform these tests in his shop. There is no one test for leather. If you showed it to him, he rendered an opinion. If he looked at it under magnification, felt it, poked it, and other such things he really was making a statement of his opinion.
It can be extremely difficult to discern some imitation leathers from actual leather, even for an expert, even in person. I am merely giving my impression of what I see in a picture.
I will be interested in seeing more opinions about this case. In particular I am interested if anybody is aware of It's George cases without a logo.
Personally, I have been studying case making and leatherwork intensely and do not recall unmarked It's George cases, leather or otherwise.
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