If they broke the law, why did the government return the wood to them?
The government didn't return the wood at issue, it only returned the East Indian Rosewood, most of which was seized at the Dallas airport from Luthiers Mercantile.
The two civil forfeiture actions were U.S. v [Madagascar] Ebony Wood in Various Forms, Civil No. 3:10cv00747 (U.S. Dist. Ct. Mid. Dist. Tenn.), and U.S. v. 25 Bundles of Indian Ebony Wood, Civil No. 3:11-cv-00913 (U.S. Dist. Ct. Mid. Dist. Tenn).
The government didn't return the Madascar Ebony or the East Indian Ebony.