SION ULT HACK?

just got out of a game playing with a sion (their in game name: hmoobtank ) and he had total control over his ult, he was running circles around the enemy inhibitor and it's just ridiculous, i know i'd hate to play against something like this because it is some sort of in game issue i don't know how he does it but maybe a riot employee can play back the game some how?