Originally Posted by
CENTRAL
It's a countersunk hex screw 3x12mm. The hex has become totally round...
I would try and drill it then. The rounded hex in the head will help you keep the drill centered. Go with a drill just slightly larger than the bolt (1/8 should do) and just go slowly. You should be able to get the countersunk portion to pop off and still have enough of a nub remaining to grip with a pair of pliers. Apply some heat to the nub before you try to remove it to break down the thread lock.