[GAMEPLAY] - Vel'koz tentacles disappear until death

After I died to Talon, Blitzcrank and Lulu, Vel'koz's tentacles disappear the moment he respawns and only come back after he dies and respawns. Using abilities or autoattacks don't seem to show tentacles either. This was a game I played a week ago, during Twisted Treeline: Hexakill. I wasn't the only not seeing the tentacles as both my team and the enemy team confirmed they weren't visible. Not sure how to replicate the bug.

EDIT: Bug can be seen starting at 0:28.