Can we reverse if the evidence supports the reasonable inference that by giving a nod to a witness that the witness was guilty of perjury?

Even if one were to grant Flint the proposition that his nod is as indicative of guilt as of innocence, we may not reverse if the evidence allows the reasonable inference that the nod indicates his guilt: "We respect ... the exclusive province of the jury to determine the credibility of witnesses, resolve evidentiary conflicts, and draw reasonable inferences from proven facts." United States v. Boise, 916 F.2d 497, 499 (9th Cir.1990), cert. denied, 111 S.Ct. 2057 (1991) (citing United States v. Goode, 814 F.2d 1353, 1355 (9th Cir.1987)). Plenty of evidence supports the reasonable inference that by his nod Flint encouraged Brister to commit perjury.