Where does the bend start? Is there some straight area where the stud meets the head, or does the bend start right at the base? The stud is trash at this point, but they're cheap. Your biggest concern is getting it out without damaging the head. The jammed nut or stud extractors work fine on a straight stud. You're are applying an inline rotational force. On a bent stud, this could act as a lever, possibly breaking the threaded mounting hole. You might want to try a pair of vice grips with the sides of the jaws flush against the head. The bent stud would be angled across the jaw faces. Basically you want the straight part of the stud still in the head to be at a 90 degree angle from the jaws. The goal is to turn the treads inside the head in a straight rotation without any angle.
If the bend starts inside the hole where you see a gap on one side, and it is jammed tight on the other, I might consider trying to straighten it some before removal, Heat the stud right at the base, and then slide a small dia. pipe over it. Apply gentle pressure. You're not trying to straighten the stud to reuse it. Your goal is to get out of the head cleanly.
Think of an arched rod inside a straight tube. As you rotate the rod, it going to push against the tube at the ends and middle. That's kind of whats going on if the bend starts down inside the hole.
Post a close up picture of the stud if you can.
Good luck