Li Baizhen remained close and also refused to help him pass any messages. What could he do?
Li Baizhen's reasoning was indeed logically sound.
What if the information leaks? Your human identity could be compromised, and instead, it might lead to the death of your second elder sister.
Once he gets in touch with your sister, the demons' attention will focus on her, thus endangering her.
And if your sister does not keep the secret and you disappear here while she remains carefree without any worry, any investigation into this would be filled with loopholes.
Anyway, all reasons piled up, and they oddly made sense.
Despite Fang Yu now mingling between the Foolish Underworld and the demons, and seemingly doing quite well.
In reality, in front of the entire Foolish Underworld and the large group of demons, Diao Deyi is practically invisible.
Unnoticed, with no slips, hence why he could blend in well.