Pateneit is the name of the Egyptian priest that Solon spoke to in Sais, according to Proclus (5th cent. AD) in his Commentary on Plato’s Timaeus (Vol I). He adds that he also spoke to two other priests, Ochlapi at Heliopolis and Ethimon at Sebbynetus. However, Plutarch (2nd cent. AD) gives the names of the priests at Sais and Heliopolis as Sonchis and Psenophis respectively. It is frustrating that we no longer have access to the sources used by Plutarch and Proclus, but they do seem to enhance the provenance of Plato’s account.
The Thomas Taylor translation of Proclus’ commentary can be read online(a)(b).
Sonchis was the elderly Egyptian priest of Sais, who, according to Plutarch(a), related to Solon the story of Atlantis as recorded in their temple. These conversations took place around 590 BC. Additionally, Plutarch records that Solon also spoke with Psenophis a priest of Heliopolis.
Lewis Spence notes that Clement of Alexandria also gave Sonchis as the name of the Egyptian priest who related to Pythagoras details of the science of the Egyptians.
Another name suggested by Paulo Riven is that of Udja-Hor-res-ne (Wedjahor-Resne) which might relate to another priest or an alternative name for Sonchis. This person was not only a priest and physician but also an admiral. A headless statue of Udja-Hor-res-ne is to be found in the Vatican Museum. I would urge caution regarding this identification.