Definitely not in the brisket. I'd say 100% fatal shot based on several moose that I have or have seen shots placed very similarly on. Lungs and liver most likely. If he was quartering away, probably would have got some heart in there.
The worst deaths and recoveries I've seen on moose, including one my partner killed 5 days ago, are high shot placements, midline of the animal and up. There are a lot of voids in the top half of moose that either won't kill the animal, or won't kill them quickly. I always exaggerate my shots low on moose for a few reasons, quicker death and better blood trails. High shots on moose usually lead to a lot of blood pooling in the body cavity and crappy or nonexistent blood trails. High double lung shots can be very problematic to follow even if the animal dies relatively quickly. It is remarkable how much ground a moose in flight can cover in a very short period of time.
On my moose this year I put two rounds from a .300wm in basically that same spot but with more of a broadside presentation and blew the heart to shreds. The 67" with a massive body bull took three steps and was dead in seconds with a shocking amount of blood loss.