Almost identical situation just occurred on a lease where I hunt. A friend put an arrow in the right shoulder of a buck. The arrow also broke off about 5" above the broadhead. This buck did not go down and although we were able to track him and saw him 2 hours later, we could not get another shot. 2 1/2 weeks later, another hunter on the same stand as the original hunter was able to get a good clean shot at him. He was limping badly, had lost weight and had a broken shoulder. I don't think he would have lasted a lot longer. But he did stay in the same area and went back to his old feeding routine. Possible, spending a few days hunting the same area might be productive.