I stand corrected. It looks like when sorting by any of the 5 Overall Score columns, or by the First, Second, or Third columns (the number of times a player has ranked 1st, 2nd, or 3rd), they don't fall back on the player's name to break ties. I believe that is a bug.
Which means the sort order is with respect to ties when sorting by one of those columns is non-deterministic. Actually, it probably is determined by how the player list is stored internally, but for practical purposes it might as well be random.