[Gameplay] Jarvan turned invisible

I was playing a game as Poppy vs Jarvan. He went into a bush where i had no vision. Flagdragged on me and i immediately used my W, interupting him, making him go invisible for around 5 seconds. He was flashing and aa'ing me, but i could not see him. I tried downloading the game, to see if it was visible there, but it wasnt. I aslo asked Jarvan about it, but there was nothing on his end. Both me, and my midlaner saw this visual bug. Havent been able to recreate it either