A few options.

Dremel tool through the screw

Hammer and rod to push it through

Another screw, in the screw, but with a counter spin and a wing nut. Only works if you can get a small enough counter screw that won't break.

If a portion of the screw is grippable, try some rubber to increase friction and surface area and a wrench of some kind. Or your hand, that would work too.