The 3D gun issue has been highly politicized. Do you think that the government could have framed this guy? If the FBI is involved, I’d be very skeptical.
At this point, if the FBI is involved, we should presume that it is false or tainted until proven otherwise.
Anything is possible, including that this is complete fiction and nothing happened, and including that Cody met up with her 18-20 y/o sister and the Left is swapping in the younger sister to represent his tacky behavior as a crime. I think it's more likely that she is 16 y/o (under 18) and represented herself as 18 both online and in person, most likely with some coaching and assistance specifically to entrap Cody Wilson. "Want to make $10k? Create an account on this website, contact 'Sanjuro', and meet up with him." That would be a felony if a decent person set it up, but when the Left does it, there are no repercussions.