From potentially incorrect memory, one can find the actual optimal solution pretty quickly, but that needs a giant lookup table that functions like an end-game table. Their lab might not have a machine with enough memory. Keep in mind that it would be a net loss if the solver took even 15ms longer.

Or 26 in the quarter turn metric http://www.cube20.org/qtm/ which is probably what matters for a robot, since 180 degree turns take longer than 90 degree turns?