Checked bag fee waived

The checked bag fees will be waived for all elite members and guests traveling on the same reservation (excluding group reservations) for travel in the Main Cabin on flights marketed and operated by American Airlines or marketed by American or American Eagle. The number of waived bag fees depends on your elite status.

Oversize or overweight bags may incur additional fees.

OP the best you can do is get 5 others their 1st bag free, if you go with booking 9 via the group desk only you will get a free bag. Id book 6 (including myself) put it on hold and book the next 6. Only way to know if all 12 can get on the same flight