How did the AI get the missile? She's a hologram. Did she tap into its electronics and had it flown to her base, or did Emmore and her brother take it to her?
When Emmore's brother ambushed Jaha and his group he told her to search them for tech. What would Grounders do with tech, when they believe a legend that if a grounder picked up a gun Mount Weather would wipe out their people.
Hopefully, Jaha will ask this particular question so that we get the answer. I hope they don't just forget or breeze over it like the scene where Jaha and Marcus reunite in the Grounders dungeon. We know how Jaha made it down but I thought at least they would've shown the scene where Marcus asked that question.