Got all three Exotics after completing the Legendary Campaign with the respective Classes with zero issues. As a quick reminder, the Exotics are not awarded immediately upon completing the final Mission; you will have to travel to the Cantina and take a seat at the bar to receive the reward. If you don’t receive the prompt to claim the Exotic and don’t feel like replaying the Campaign to figure out which Mission you missed, there is an irregularly shaped Chest that occasionally spawns on a table to the right of Aunor that will allow you to purchase for the Class you are currently playing. (΄◉◞౪◟◉｀)