Hearing parent here.
Few questions:
How far away from the school do you live?
Can you go visit with her like, after you get off work?
That might ease her missing being home.
I agree with making the deal to give it a few months and I'll tell you why. Though I am not deaf, I was "weird" as a child. I didn't make friends easily. My mom sent me to overnight camp. I wrote her letters EVERY DAY saying that I wanted to come home in the first week. The second week, she didn't even hear from me because by that time I had made A(one) friend and got into the activities (while, the first week I didn't even try to participate). Third week, I was sad to leave.
Same thing happened when I went off to college. I grew up in PA, but my mom convinced me to go to her alma mater IN FLORIDA!! Again, away from the only friends I had and away from my family. I was very non-social for a few months, but after while, again, I made a friend...or two...or 20! I went home for the major holidays the first semester, but after Christmas my freshman year, my family and friends were begging me to come home! LOL
I would go home with my new friends who were from Florida or Georgia.
All that to say, give it some time and BOTH of you will become more comfortable knowing its what's best for her (is it?).
In today's time, with things like email, MySpace, video and VRS, you can still stay connected (talk every day).
I would let her stay in the school for the school year unless I was unhappy with the curriculum or how she was being treated. Usually, by the end of the school year kids have a buddy that they will miss during the summer.
And will want to return to be with their friend. If not, then at LEAST she tried it and gave it a real chance.