The clarified tweet is also different than what I've seen claimed happened. The quotes I read in an article from the supposed Elon e-mail make no mention of any 'child event', rather they are Elon berating the employee for missing a meeting. Paraphrased: 'We're changing the world here, get your priorities straight.' Elon may have sent the e-mail before knowing why the guy missed the meeting, or the guy who missed the meeting never told Elon why he missed it. Or those e-mail quotes are in no way connected to any employee having a baby.
The media may also be doing what it so often does and misinterpreting/misrepresenting what's in the book.