I'm so sorry for your situation, this is tough for everyone involved. Death of a close family member is hard enough alone without adding affects of sobriety into the mix.
I'm sorry I don't have any profound words of wisdom as I have never been in this situation. It seems 'positive' that he admitted to feeling like a drink as he left but backed that up with the fact he had tools to help with this and was willing to use them. He has a good friend who has been in a similar situation who will hopefully call.
I guess all you can really offer him is emotional support and let him know you are 100% there for him, and the choices he makes in terms of his sobriety are his- you can't control this. I hope for everyone's sake that he can make it through this really difficult time and stay on the right track as in the aftermath that would be a huge achievement for him.
Sending you many hugs and hoping you and your family can get through this very difficult time