I’m not terribly familiar with the specifics of the deal but IIRC there’s a penalty clause that’s dependent on who, ultimately, backs out of the deal. It seems like Musk is angling to get Twitter to pull out and Twitter is doing everything they can to engage with Musk’s requests in “good faith” so he can’t claim Twitter has constructively backed out— a bit of M&A malicious compliance/a game of chicken, I believe.