Stuck chainring bolt

I'm in an odd situation; my chainring bolts are all loose, so the ring is wiggling side to side by a couple of mm, but they're also all stuck fast in that I can't undo or tighten them.

I don't want to drill them because I think they'll just spin in place, and the bolt tool I bought the other day won't properly fit on the back. Are singles different shapes? I thought they were all the same.

Advice? Help? Pretty please...

singles usually have less height,make sure the ones you have arent bottoming out