Stories from the Outlands - Promise

As for the theories:
- Kuben Blisk didn't exist during the events of the trailer

- Horizon's assistant is extremely likely to be Ash (when she was a human)

- Horizon's son is dead in the current timeline, however there is a possibility she can talk to him in the past with the Branthium crystal

- Viper is a robot, cyborg or simulacrum so it is possible he is the man who contacted human Ash and asked "Do you have it?", even though the events of Titanfall 2 take place 40-50 years after the trailer

- Revenant has no involvement whatsoever with Ash or Horizon, at the time of the trailer he was still a Syndicate Servant going around murdering his boss' enemies

I think in the Season 7 quest, Horizon is going to implore the Legends for help in keeping her promise to her son, and she may or may not have a run-in with Ash.