Tryndamere can be killed while in his ult

I didn't experience this myself, but this was explained to me by a Tryn in my game. I was asking why the enemy Warwick would buy the jungle item that gave his smite flat damage and a slow on enemy champions, instead of the item that marks them (as it is clearly the better option) and the Tryn states that it was for him. While in his ult form and at 1HP, Warwick could smite Tryn and kill him instantly. I saw this happen multiple times in the game, and although we brought them down to a naked nexus, we ended up losing the match because of this as our fed Tryn couldn't survive a fight because of this glitch abuse.

The enemy Warwick was well aware of what he was doing, and was abusing it to make sure Tryndamere's ult would be useless. And yes, we ended up losing directly because of this, right as our Tryn was about to finish the game with his ult keeping him alive, he gets smited and dies not even 2 seconds into his ult. They finished the game soon after, and although all of them lost or barely went even in lane, they did the obvious thing and BMed out of control (usual stuff, calling us noobs, you know). I'm pretty sure this is a serious bug that needs to be dealt with.