If Apple has receipts, this could spell the end of OpenAI anyway. Even if Apple doesn't go to trial, at minimum, OpenAI will need to discard any work that even remotely touched or was influenced by Apple's IP here. If it was shared broadly within OpenAI across multiple projects, it could be quite substantial. Fruit of a poisonous tree and all that.
In the not-so-distant past, Uber's head of self-driving was indicted and sentenced to jail time for similar conduct. The criminal case didn't start until ~2.5 years after the civil case was filed.