"The defense recently learned that the government has possessed exculpatory materials since August 2023 that go to the heart of a fundamental issue in this case: whether a noncustodial cryptocurrency mixer is a 'money transmitting business' for purposes of 18 U.S.C. § 1960," the filing said. "The government’s failure to produce those materials in the fall of 2023, when Roman Storm was indicted and first appeared in court, constitutes a Brady violation that has materially prejudiced his defense,"