Yeah, I noticed the differences in the facial structure and skull caps right away. Your buddies buck comes down to a point and has that high, narrow ridge on his nose. Your muley has more of a barreled nose. I didn't want to get to carried away commenting on them but they are different but both are great animals.
It's funny you should mention your brothers buck getting torn up. I had a buck get torn up after I shot him like you were describing on a dec. hunt on the east side. A second buck followed the same trail that my dead buck was laying on. He was a 30"+ 2x3. His fork side tines had to be close to 24" long. When he saw my buck he just put his head down and hit him...hard. At one point, he ran a tine all the way through his body starting behind the shoulder and ending just under the skin on the opposite side. When he brought his head up, it flipped my deer through the air like a rag doll. He also chewed his nuts up pretty bad as well. This went on for 45 min. to an hour. His bottom fork tine was stained dark red when he finally decided my buck had enough and I was within 15 yards of them. I'd never seen that or heard of anything like it since. I had some cape damage but didn't lose any points off my buck.
Congradulations again on a great hunt.