Use your burner phone that is labeled "DANGER" and call 231-9965.
Another burner phone will route the call to one of Xinshen's men.
He will use his phone to call Xinshen and set up a drop-off point for your handwritten message asking to talk.
Make sure to encrypt your message.
From there if Xinshen wishes to speak, you will be given a number which will direct you to a room in Zaido.