Shen Wei sometimes has not the greatest judgement! This is actually a prime episode for this. There are people who will die at the wedding in the next ep in part because he didn't tell Zhao Yunlan who the real Dixingian was here.

I mean, it's not that I like it in the sense of "yay bad judgement!" but Shen Wei not being always right and knowing, I like for the narrative.

(That being said, the specific cases of "rapist college guy" and "abuser" are kind of prime examples of "people don't see it and are shocked when stuff comes out". And a suits wearing researcher guy in particular...)

(I'm not in a good position to verify ep numbers so please edit 'next ep' type mentions etc. in your head as needed. Somewhere in this arc!)