In 2012, Bush admitted that he returned the trophy back to the Heisman Trust. However, the whereabouts of the trophy has remained a mystery. Well, until today.
From the Washington Post:
The Trust no longer acknowledges Bush as a Heisman winner and is secretive about the trophy’s location. Henning said the trophy has neither been destroyed nor reissued — rather, it’s in a storage unit in the New York City area, alongside portraits and valuables the Trust no longer had room for when it moved from the Downtown Athletic Club.
So that's where the Heisman Trust stores all of its junk.
Interestingly enough, the storage unit also contains Eddie George's original Heisman Trophy, which was damaged by an airport worker immediately following the ceremony.
Via For the Win