Tryndamere game breaking bug "Poor Tryndamere"

I didn't have video but all of us in game witnessed it 3 times in the same game so we think we narrowed it down to what's happening. When tryndamere ults and gets rammed into a wall by poppy's e. A karma can kill him with one of her abilities. I don't know if it was one specific ability "the snare" but the snare did kill him one of the times it happened. One thing is for certain it was a guaranteed he was dead if poppy stunned and karma was near by. This all happened when he was already invulnerable for only 1-1.5 secs. There was one time where he hit his invulnerablility right has he died and it took his cd and made the sound animation. Just give it a test and see what you guys come up with. If this helps we played the game around 4 am central time on 2/17/2016 it was a 47:52 sec game.