Just do it. You can call and let him know you're on your way once you have everything set up - that'll give oW a chance to skedaddle if she's there. You are the mother of his children, you have a right to be there, and frankly, he can never fault you for wanting to come and be there for him, but he might fault you for not showing up, even though he isists he doesn't need you.
If he gets bad news, don't you want to be at his side? (Although hopefully he won't).
