@oristarA,
Yes, "fsck" does stand for file system consistency check. It is a inside joke for software engineers.
Fsck is a common tool for checking a disk drive for errors. Mickey-Sakke is a method to maintain encryption keys.
The phrase "for fsck's sakke" is a play on words since it is similar to "for ****'s sake" (a common vulgar phrase to express disdain).