[Gameplay] Skarner ult activates Colossus incorrectly (?) when target blinks away during cast

CotC procs when Skarner's ultimate plays the animation sound during the cast time, however the target (Ezreal in my experience) used blink to get away and isn't actually suppressed. I assume this isn't intended? It's happened to me and I've seen it as a spectator as well, he clearly gets the green Colossus shield and it goes on cooldown.