In an alternate Reality, R. Gohrlay's brain never recovers and is not repaired. R. Nahan continues to receive copies of the positronic circuits that were created in an attempt to "download" Observer Gohrlay's mind. R. Nahan manages to achieve a human-like mind with telepathic powers similar to those that R. Gohrlay had. He goes on to develop time travel technology and eventually travels back in time to repair R. Gohrlay's damaged brain circuits and create the Reality that is depicted in The Start of Eternity.
In the "Nahan Reality" where R. Gohrlay's brain is irreversibly destroyed, the existence of the star Nemesis is discovered by astronomers from Observer Base. R. Nahan uses the planet Erythro as a place where he can experiment with genetically engineering cells so as to give them the ability to communicate by means of T-particles. As depicted in Asimov's novel Nemesis, humans travel to the planet Erythro and some of them begin to have telepathic contacts with the "collective consciousness" that Nahan created there. This allows Nahan to realize that some humans have a latent telepathic ability. When Nahan travels back in time to repair R. Gohrlay's brain, he provides her with information about gene combinations in humans that make possible a limited amount of telepathic ability.
It turns out that the types of genetic modification favored by the Huaoshy select against telepathic communication in favor of linguistic communication, so they have never realized that telepathy is possible. It is only because positronics was studied by humans at at Observer Base on the Moon that telepathy was discovered. R. Nahan's experiments with telepathy on Erythro can be viewed as the first step towards Gaia and Galaxia.
It might be fun to have the existence of "Nemesis" mentioned to Asimov while he is on the Moon. He would not be told the true location of "Nemesis" and it would not even have to have that name. Similarly, the planet where R. Nahan performs his experiments with telepathy might not be called "Erythro". Asimov would simply be told of the idea that there was a world where telepathic signaling between biological cells was first studied. After returning to Earth, Asimov was free to create his own story about such a world.
Update. I had Creal mention a secret star called "Nemesis" in Chapter 9. The type of star and its location are not known to Creal, only the idea that it ways where positronic robots (R. Nahan) first experimented with was to strengthen telepathic signal exchange between living organisms.