[Gameplay] Rumble can kill tryndamere under ultimate

Rumble can kill tryndamere even though he used his ultimate. I didn't identify the spells that can kill him but i think the equalizer does and an other spell( i died once without his ultimate used). I don't know if it always happens, but both times i died, kalista just popped her e that was supposed to kill me without tryndamere's ult when rumble killed me at the middle of the ult duration (it may have no link with the bug).

1. Fight tryndamere/rumble 2.tryndamere uses his ult
2. rumble uses a spell that hits tryndamere and he dies probably not 100% I'll try to get more information testing it in custom (if i find someone to do it ^^). I got the replay of the game (it happenned twice), where can i post it?