[2022] Game-changing bug in game 3 C9 vs CLG

In game 3 of the series, the game was very even. CLG 1k gold advantage, 2 dragons to C9's 1. Then, a pivotal team fight happens in mid lane. Fudge's Kennen pops off to wipe CLG. C9 are now firmly in the lead for the rest of the game.

Except... CLG had 3 exhausts. One each from top and support and a spellbook exhaust on mid. How could Kennen get the ult off with so many exhausts?

Enter: riot games spaghetti code. Dhokla exhausts Kennen. 2 seconds later, Kennen flashes in and gets exhausted by Palafox, then Poome. A fraction of a second later, the exhaust is gone. Kennen should have been exhausted for the full duration of his ult combo, but a bug made the exhaust instantly disappear.

https://youtu.be/rEY0-WjRTZk?t=1653

Edit: Supposedly this is just a spectator bug, but someone did math in the comments and the math makes it seem like it was an actual bug (kennen did full dmg).