When you had the amount of torque on it that was able to bust it off like that you very likely twisted the ball end around in hex and deformed the hex enough that the ball is now sitting partially in its own pocket.

Knowing my superglues from model building I can tell you that for this use it ain't all that super and it is not going to hold well enough to get out past the deformations in the hex you produced.

I think you're stuck with dwood's suggestion to carefully grind away the upper part of the ball and open up the mouth of the socket in the screw until the last part of the ball can fall out. Then hopefully there is enough of the hex left to get a proper allen wrench in there and take out the bolt so you can replace it. If the hex is damaged enough that you can't do this then the right size EZ-Out may work or you can then drill out the head of the bolt.

It'll be a fussy bit of work and likely use up more than one of the little grinding stones that fits in there. The hardened allen ball will not allow you to use any cutting burrs so stick with the grinding points.

A hard lesson to learn isn't it.....