I'm sure there's a non compete clause in his employment

Unlikely, non-compete clauses are not enforceable in California.

Not for principals/ founders. The law applies to employees.

That would be happening but Elon won't want to be overshadowed

And then in a plot twist it turns out Elon was the AGI

Or Musk returns to the board of OpenAI after a hiatus.

Never, Elon despised Sam's pivot from non-profit to for-profit. He invested 100M in the beginning.