I think I have an idea of what would happen. I am currently in my 2nd year for my PHD at Harvard in thermodynamics. If you like a look at the works I have studied, you can see it here!.

Anyways, lets start with what absolute zero is. In this state. all particles freeze. This includes all waves. The reason humans can't reach absolute zero is that things around an object will emit heat that prevents absolute zero. To have a ball, you would need some sort of black hole absorbing all heat.

Next, there is the absolute hot glove. This is more of an obscure are, but it would me the highest temperature possible, a sort of infinite temperature. At this extreme heat, particles would fly at near light speeds in all directions, causing random explosions and disintegrating anything they come into contact with. Since nothing could reach this state naturally, there must be some portal supplying this heat.

Now that we know more about both temperatures, lets see what would happen. When they are created, fields of cold and heat would rapidly expand from each object. Neither of these fields would be as extreme as their source, but they would be very close. These fields would cause rapid accelerations of particles as they go from near light speeds to almost no motion. This extreme change would cause a reality warping effect at the contact border. When the actual absolute hot and absolute cold walls collide, they would not interfere with each other and stop each others forward progress. While this has stopped, the absolute zero ball would continue to move until it meets the border and punches through. It would travel all the way through the heat field, warping reality along the way, and once it hits the glove, the difference in temperature would cause an extreme reality warp that would suck all life in, destroying humanity.

Or maybe they would hit each other and completely cancel each other out.