An interesting factoid RE Osburn's report of cartouches being found at apparently the entrance. Seems hard to believe it would have been missed by everyone of his era but him...
It's all a little strange.
Vyse entered the pyramid in 1837. The KK cartouche must have been visible as Osburn claimed to have seen it only a few years later.
One would think that upon entering a "tomb" and seeing an inscription on the stonework - in this case a cartouche - symbolic of a pharaoh - one would logically assume that this cartouche would be representative of whoever was entombed. But Vyse ignored it.
Vyse was only satisfied when he allegedly discovered the simple Khufu cartouche in Campbell's Chamber. If Osburn, in 1845, did not know the difference between the two cartouches, how then did Vyse, in 1837, know that the simple cartouche represented Khufu, but the KK cartouche must, in his opinion, be some other entity not connected with the pyramid?
What would it matter if Vyse declared to the world that he had discovered the builder of the pyramid and that his name was Khnum Khufu? What's in a name?
One possibility is that Osburn, for whatever reason, did not see the KK cartouche at the entrance, as claimed, but was lying, although he certainly knew of such a cartouche, as evidenced in his work. And why wouldn't Vyse and others, have brought this discrepancy to light upon publication?
If the KK cartouche was at the entrance, how was it not seen, and recognized, by earlier explorers of the pyramid leaving Vyse with no claim to fame?
It's a bit of a puzzle.