Both of these guys were offered a chance to return to Star Trek, but only one agreed.
Frakes has directed fourteen episodes of the Star Trek franchise, along with two of the films (including the very well-received First Contact) and multiple episodes of other shows. His most recent credits include Falling Skies, Agents of SHIELD, Burn Notice and The Librarians. He is noted for his ability to find unusual angles to shoot familiar sets from and for a lean directing style, leading to his nickname "Two-Takes Frakes".
Frakes isn't the only Next Generation castmember who was offered a chance to appear on the new show. Michael Dorn, who played Lt. Worf on both The Next Generation and Deep Space Nine, was offered a guest role playing Worf's grandfather. However, he turned them down after they offered "less than one percent" of the fee for his previous appearance in the franchise, in the 2002 movie Star Trek: Nemesis.
The first half of the season will start airing on 24 September. CBS will be airing the first episode, with the second episode available immediately thereafter on CBS All Access; Netflix, which is airing the show internationally, will release both episodes together the following day.