So been thinking alot about Shen Wenlang and how there is a lot of talk about how dumb the man is when it comes to Gao Tu. @heretherebedork has made some brilliant posts really analysing that and I think they are right.
Wenlang believes and trusts Gao Tu implicitly. He's known him for 10 years. Gao Tu is a loyal and trustworthy secretary (and friend). Wenlang can't even comprehend that Gao Tu would not be truthful. When the picture is sent to Gao Tu he doesn't question or ask to see it. So he believes Gao Tu is a beta, he believes he has an omega. His concern is that the mysterious omega has latched onto Gao Tu and will bleed him dry. His concern is for Gao Tu no matter how badly, and boy is it badly, expressed.
He isn't putting 2 and 2 together because those sums just don't make sense to him. He's working with facts he believes are immutable.
Where Wenlang is absolutely 💯 dumb is in relation to his true feelings for Gao Tu. Yes, here the man is as dumb as a rock. He has no idea what he feels. Has never addressed it and it is only now Gao Tu is leaving that it is starting to dawn on him.