Friendly Kalista Killed Me

So I was playing an ARAM as Fiddle with a Kalista on my team. Her and I got into a fight against a Syndra and I ended up dying to Kalista. Syndra used her push ability to push us backwards at the same time that Kalista used her Q and it said I died to Kalista. Keep in mind, I was not Kalista's Oathsworn, our Sejuani was. Would post pictures, but im a noob on the pc and don't know how. I have tried looking this up for hours, with no luck. I fear this could be a new glitch that trolls would run rampant with (as if Kalista's ult wasn't troll material enough). I was wondering if anyone had any ideas on how this could have happened. Thanks!