A little late but... I've done the battle with Hedgie quite a few times until the cheevo finally popped. I've read a few guides to check what I was doing wrong, and probably the problem lied on the electricity ability splash damage, aka, the boss was too near when I used the glove to activate the statue. On my successful try, I made sure that the boss was far away at the moment I activated the statue; basically I lured him away from the statues, and just waited until he got tired and started the cooldown animation; then I moved to the statue control panel, waited for him to recover and started his animation for the rolling attack, and activated the statue on that instant. Not sure if it makes any difference at all, but I've always used different statues, which makes, counting the first obligatory one, a grand total of 5.