Tahm can't kill Heimerdinger turrets

The other day I was play Tahm kench top versus Hiemerdinger. Every time he was away from his turrets and I tried to devour the inactive turret, it would become unkillabe and stall the minion wave. It is a serious glitch and needs to be fixed. I almost lost the game for my team because I lost the ability to push the wave. To re-create; place a turret, have Hiem go far enough away to deactivate the turret, have Tahm devour the inactive turret. Viola, targetable, unkillable turret.