Can team mates trigger ezreal's w?

I was playing a game of graves and was triggering ezreals w left and right, just though it was him until this play happened. Ezreal throws w onto enemy and lands. Bard ults ezreal I grave E and auto attack enemy w triggers while ezreal was still ulted

Maybe I'm just dumb but i though this was strange.

Thanks for reading, if i'm just dumb go easy on me please :_ [sg-poppy]