Tahm Kench + Heimerdinger Turret Bug [GAMEPLAY]

So, I was playing a ranked game as Tahm Kench and I came across this bug. What happened was that I used my W (devour) on an inactive Heimerdinger turret, but the devour did act like it should. Instead of residing in my stomach, the dropped out immediately and the stun icon appeared over its head very briefly. Then, the Twisted Fate on my team damaged the turret a little, and it had just a sliver a health left. So, I went up to do a basic attack and kill the turret, but my autos did no damage. The animation and sound played, but the turret took no damage. I must have attacked it eight times before Twisted Fate went up to auto it and it died. I haven't been able to reproduce this bug. I have attached a video of the when this happened. I should also add that this happened yesterday, before the new patch.