Still broken. Nice to see this bug has been around over a year and has been intentionally ignored by the devs. It's blocking two achievements and a major collection, how in the world did they decide it's not worth even a partial fix? Do they even care at all?
Seems it is still broken, subject S is not moving, nothing is happening.
May I Suggest : 1) a hard timer that resets this quest every 2 hours. 2) a soft timer for saving the other skritt, and forcing the quest to move foreward on expiration.