Let's be fair, although Sun Bu'er is awful in many aspects of his personality and not very likable to many, he does have a point in what he just said.
The kind of advanced acupoint sealing technique that even the Seven Masters of Quanzhen can't solve, Zhen Zhibing, who has never learned any other martial arts, indeed would not know it.
But just because Zhen Zhibing wouldn't know it, does that mean Niu Zhichun absolutely would?
Hmm... it seems like he actually could!
Although this guy rarely uses it, he indeed learned the most famous acupoint sealing technique of the Jin family, the signature skill of the Dali Duan family, "One Yang Finger".
Not only "One Yang Finger", he even learned the most powerful move of its advanced skill "Six Meridian Divine Sword", called "Shaoshang Sword".
From this perspective, Old Niu indeed is more likely to have the condition to commit the crime than Zhen Zhibing.
