“Wonky” has two very different meanings. One as you said, describing something that’s just off, somehow. According to Grammarist: “ The word’s second sense is studiously concerned with minutiae. It connotes the kind of expertise that only a long-time insider within a given field can have, and it often comes up in politics, where a wonky person is one who is immersed in the details of policy.” http://grammarist.com/words/wonkish-wonky/
This definition of wonk is actually the root of the website Wonkette.