There is a chance Tutankhamun was never really out of the historical record.
The elephant in the room here is, of course, the vast amount of material found when Howard Carter excavated Tutankhamun's tomb in 1922. It will overwhelm just about anything you might find in a casual Google search, not to mention an AI summary on the subject.
So, it's necessary to find some pre-1922 material on Tutankhamun.
William Flinders-Petrie's 1896 book A History of_Egypt, Volume 2: The XVIIth and XVIIIth Dynasties is probably the state of knowledge of Tutankhamun at the time, and has this to say:
Of this reign we know scarcely anything, except from the fine tomb of Hui. The paintings on that show that the princes of the Rutennu in Syria, and of Kush in the Sudan, were both subject to Egypt, and brought offerings and tribute. This points to a continuity of Egyptian power, and shows that whatever changes had gone on inthe fall of Akhenaten's ideals, the vitality of Egypt abroad was not entirely destroyed.
Flinders-Petrie goes on to say that
The claim of Tutankhamen to the throne was through his wife, Ankhsenpaaten, altered to Ankhsenamen, the daughter of Nefertiti and Akhenaten; he may also have been descended of the royal family, though the fact that he calls Amenhotep III. his father (on the Barkal lions, B. Mus.; Rec. xi. 212)
He didn't imagine the thing that most scholars think today: Tutankhamun's father was Akhenaten himself.
A lot of the pre-1922 knowledge of Tutankhamun comes from Flinders-Petrie's own excavations at Amarna, which he began in 1891. Tutankhamun's successors, notably Horemheb and the first pharaohs of the 19th Dynasty, did their best to wipe out the memory of Akhenaten and Tutaknhamun, the best example being their omission from the Abydos King List of Seti I.
This involved disasembling their rival's buildings, and many of the stone blocks from the buildings so destroyed were reused in new buildings. Reassembled by modern scholars, their actions ironically preserved a record of Akhenaten and Tutankhamun.
(I wonder if Tutankhamun's tomb opening being buried in debris from the tomb of Seti I was all that accidental.)
If you follow some of the citations in Flinders-Petrie's book, you will see that Auguste Mariette found some
jars bearing the name of Tutankhamun while excavating a bull burial at the Serapaeum of Saqqara in 1852.
But there's something we missed in all the archaeology. All of these scholars were classically trained, and knew that the Hellenistic priest Manetho had compiled a list of Egyptian kings from priestly records. Passed down to us from some epitomes in Africanus, Josephus and Eusebius, and ultimately the Byzantine scholar Syncellus. It's a millennia-long game of telephone at every step.
Nevertheless, Flinders-Petrie goes to a lot of trouble trying to map Manetho's list to the known monument-based chronology, and identifies (p.25, PDF page 46) Tutankhamun with one "Rathos" (Eusebius/
Africanus) or "Rathotis" (Josephus), via a shaky bit of philology:
Next, Ratothis [sic] is said to be the brother of Akenkhres, while we know that Tutankhamen was the brother-in-law of the previous queen, having married another daughter of Akhenaten; the name Aten'tut'ankh (altered later to Amentutankh) may have been rendered by the orthodox as Ra'tutankh, and so have originated Ratothis.
It's a very shaky and controversial identification, but if "Rathohis" is Tutankhamun, then we have a continuous historical record of him passed down from the time he lived. If not, we have to rely on archaeology, and Mariette's report of the jars he found in 1852 will have to be the answer.