“resulting technology will benefit the public and the corporation will seek to open source technology for the public benefit when applicable. The corporation is not organized for the private gain of any person"
I don't think it is going to be hard to show that they are doing something very different than what they said they were going to do.
The charter is not a contract with Musk. He has no more standing than you or I.
He was defrauded. If OpenAI fails, there is a good chance Altman et al get prosecuted.