Dismissing Non-Dismissable crewmates

[Gammerick]

currently the I believe this only applies to Bimbofied Kiro and Bess if you complete her relationship quest

When will the option to dismiss them be added?

 

[TheShepard256]

Probably never; such options would have been included in their initial content if they were intended to be included. For bimbo!Kiro, there's no option probably because she doesn't have anywhere to go if dismissed. Neither do bimbo!Penny or Celise, for that matter; they're also undismissable, as are Olympia and regular Kiro on their respective ships only (the Sidewinder and the Blade, though Olympia will leave if you switch to another ship). Bess can be dismissed, but once you're lovers with her it's changed to breaking up with her, which removes her from the game.