'It is easier to give the advice than to receive it'. Having said that, I'm giving few. I feel very sorry for what had happened. But I see there's still a hope as the case is still within the school, and till now the school has the power to determine. I'd recommend writing down the main points that you're going to discuss with Mr. President. Since you know that mistakes have been made by your side, I'll not try to argue or try to justify my actions by saying that other int'l students are doing the same or warnings have not been given. But rather I'll try to focus on few positive sides like others also recommended: boasting about GPA, talking about family conditions and their great hopes from you and the pain they'll get if you had to return, the lessons that you learned from this and talk about all the pains and sleepless nights that you've got from this; moreover, don't forget to add that you're never gonna do this mistake again and confine yourself within on-campus work. In my opinion, talking about our poverty may give the impression that you may go for off-campus works if you're acquitted. You've to impress and try to prove themselves that you're never ever going for off-campus works again and this is the dumbest mistake of your life, and beg them for one more chance. You can also add how your life is going to be wasted if you would have to return home as you won't be able to focus on studies again as everyone will know there you returned there without completing your studies. Not even by mistakes, you ever mention about the mistakes of pakistani or the immigration lawyers that you've tried to contact. You know better than us as you're in the situation. So my last advice would be to use our suggestions that you think is going to help the best for you.