[ALIBI]

The rules seem to indicate that you must let go (not be in contact with) the trackball sometime before, during or after it completely crosses the finish line once you do whatever it is you do to get it over and to count it must touch either the floor or another robot before you touch it again.

When the trackball is completely past the finish line, if you have not all ready let go of it, you must do so now. Then, before you touch it again, it must touch either the floor or another robot.