The most plausible explanation, based on the facts so far provided, is that it is Harigai, and he is not happy with how the game/company turned out and does not want to be reminded about it anymore.
The fact is that, if there were only one AGI that were ever to be created, then yes it would be quite unlikely for that to happen. Instead, what we are seeing now is you get an agent, you get an agent, etc. Oprah style. Now just imagine that a single one of those agents winds up evil - you remember that an OpenAI worker did that by accident from leaving out a minus sign, right? If it's a superintelligence, and it becomes evil due to a whoopsie, then human extinction is now very likely.
Facebook, Instagram, Twitter, and Tiktok all fulfil the 'whatever topic I am interested in this second, there are videos about it' property, though admittedly they do not have near as much meritorious long-form content as YouTube.
It is starting to become clear to more and more people that Sam is a dyed in the wool True Believer in AGI. While it's obvious in hindsight that OpenAI would never have gotten anywhere if he wasn't, seeing it so starkly is really rubbing a lot of people the wrong way.
Well, in the world where AGI is created and it goes suboptimally, everybody gets turned into computronium and goes extinct, which is a prospect some are miffed about. And, in the world where it goes well, no decision of any consequence is made by a human being ever again, since the computer has planned every significant life event since before their birth. Free will in a very literal sense will have been erased. Sam being a true believer means he is not going to stop working until one of these worlds comes true. People who understand the stakes are understandably irked by him.
If you are in the US you can look up their official service address through the secretary of state for the state that you will be filing the lawsuit in. There is never a need for them to specifically provide you an official address.
And if you're filing a state case, and you know which county they are in, call the Sheriff. Every Sheriff's office deals with legal service on a routine basis. I've paid the Sheriff many times for serving complaints.