I can not give you more information about my relative without asking the person first. However, I don't think this information will be of much use to you because my relative wasn't detained at port of entry.So even though this case doesn't exactly match with your mother's case, its still a deportation case and in terms of complexity, my relative's case should not be any lower than yours.
The big point here is to get a great lawyer who deals with deportation issues much more than regular immigration matters.I think the lawyer I mentioned above is a great choice. This lawyer is a chairperson of ICE detention and removal committee of AILA.You will be in good hands.I know from meeting her that if she thinks your mother's case is weak, or that there is no chance to win the case, she will not take up the case and waste your money.I guess she has her reputation to protect. :)

As a disclaimer I say that I am not a Lawyer and this is a personal suggestion.
good Luck