In the last raid tournament a friend attacked my defense and sent me a video of it. That attack did not show up in my list. At that point i had received less than 30 attacks total so as far as i understand, it should have been there. The same thing happened to someone else in my alliance. At the end of the tournament my defense was supposedly attacked more than 80 times, while the attack of my friend never showed up. To me this suggests that there is some error in the attack to defense assignment.