That shoulder blade is a funny thing I have hit them a few time in 45 years and seen arrow do diffident things. Hit a big bucks shoulder once with a 65 lb recurve and the 2117 alunimun arrow and the 140 grain broadhead went in broadhead deep and bounced out. Once with a 70 lb compuond and a carbon arrow with a 85 grain broadhead it shot through a 250 lb field dressed buck and hit the shoulder blade "paddle bone" on thet other side and shot through in and the arrow stuck in the ground. I hit a big one once and the carbon arrow went through the shoulder blade about 10 inchs and broke off and I got the deer. I can only remimber losing one hit in the shoulder blade. I see a bowhunter shoot a carbon through a doe once the carbon arrow broke the leg bone on exit the bone was sticking out the hole, A friend shot a buck once through the front part of the paddle bone angled in to the lungs, but man it hit him hard I was 200 yards to 250 yard away from him in my stand and heard it hit him, He did get a pass through the carbon arrow was laying on the ground and he didn't go ever far. Seen a friend hit a bull elk once in the shoulder blade at about 10 yards and the carbon broke of leaving about 8 to 9 inch in the elk, so must of made it through it. We didn't get him, but now I'm talking about with 65 to 70 lbs bows. From what I have seen over the years one time it will do one thing and the next time not.

Sorry about your lost, like they alway say some times #@#! happens, but there have been bucks taken before with a broadhead in there shoulders blades that they have been carrying for a long time. Maybe he will live to be hunted another day.