Given the fast turn around on Jewish funerals the family understands not everybody can be there. I’m sure they’d like him to attend but 2 days is a tough turn around. He’ll get there when he can, they’ll commiserate. Adults understand that there are things you can’t attend.
making a Shiva call is more personable and is a Mitzvah, perhaps that is his plan.
*Shiva= mourning at home after the funeral for 7 days(we don’t have wakes)