It is very unfortunate, because the Singapore Civil Service prides itself for being knowledgeable, efficient, effective and with integrity.
The worse the PSC, Director of Prisons or Commissioner of Prisons, should do, is to admit that there was a mistake, that it will never happen again, pay the compensation to all those prisoners who have been caned more than 24 strokes, whether he has initiated any legal action.
That is fair and just, morally right, and what integrity compels them to do (when no one is watching).
Otherwise, whether or not they believe in God, I believe that most individuals with morals and conscience, will not be able to sleep well at night, and die peacefully, knowing, whether or not after the fact, they have done wrong by caning more than 24 strokes.