Recklessly or negligently placing oneself in a situation where duress is probable negatives the defense.
Absent a request for special verdict, acquittal for conduct later found by a preponderance and used in sentencing does not imply a theory of the crime that amounts to a vindication of the conduct.
http://www.ca2.uscourts.gov/decisions/isysquery/05194beb-c7ca-4533-89f8-3cdc4043f522/7/doc/16-2765_opn.pdf#xml=http://www.ca2.uscourts.gov/decisions/isysquery/05194beb-c7ca-4533-89f8-3cdc4043f522/7/hilite/
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.