The actual statute is crystal clear.
Seeing as she had sufficient legal representation to appeal the case, I conclude any attorney writing the appeal would point out the plain statute language as one of the questions on appeal. As the question of private property was never even raised in the opinion, I can only conclude this issue does not apply to this case.18 USC 922(q)(2)(B) Subparagraph (A) does not apply to the possession of a firearm—
(i) on private property not part of school grounds;