Liu Dong Ming was indeed here to bring some damage to the Ji family, Liu Fei Fei was simply a pawn on the chessboard but Ji Xianglan was different, he was Ji Mo's right-hand man and did all the dirty dealings for his cousin behind the scenes, he was even responsible for taking care of Ji Mo's mess and was one of the very loyal aides that Ji Mo had on his side.
If he was to take Ji Xianglan it would be similar to cutting Ji Mo's right hand and as soon as the news of Ji Xianglan getting punished goes out, everyone will start thinking twice before coming to support the Ji family. After all, Ji Mo couldn't even protect his cousin in front of Liu Dong Ming. How was he supposed to be trusted?
But if he refused to drink this wine that Liu Dong Ming has offered him, Ji Mo was certain that the next time he will be handed poisonous wine instead! Liu Dong Ming after all was not a man who would let anyone off without punishing them if they do wrong to the Liu family.