Kalista ult not firing

I was logged onto my file of league and playing a ranked match of Summoner's Rift on the non-PBE client. A video was uploaded to op.gg and can be downloaded from the blitz loss on the above link. It was taken from the perspective of the enemy team Vel'Koz support and is a .bat file which I don't know how to play. The bug details are as follows. I was playing Blitzcrank support to a Kalista ADC and at lvl 6 we decided to jump the Ashe with kalista's ult, only I never got launched in. The ult just timed out. At first I thought that it was my bad, maybe I was supposed to right click instead of left click or maybe I had a menu open. But 4 times during that match I was ulted with Kalista and no matter what I clicked I couldn't fire. I have no clue what caused it and don't have any friends that can go into a custom with me to test it with different champs. It might only be blitz or it might just be a kalista all around bug. The steps for the bug are as follows, from a logged in account, in a ranked (might not matter what play mode) Summoners Rift.

1. Reach lvl 6 on Kalista.
2. Blitz reaches lvl 6 just before Kalista ults (may not be a factor)
3. Ult area shows up, as does the arrow and small landing circle.
4. Click any button you want, you won't fire.
5. Enjoy trying to ult at any time during the game and it doesn't work. The Kalista didn't try to rebond with someone else and so I don't know if that would have fixed it.