be it out of orbit or torwards the planet, it doesn't change the fact that we can move deimos.
if we were to send deimos torwards phobos and make both moons fall together torwards mars, the impact would be hard enough to make the deepest crater ever on the small planet and as a bonus the metal core will give humanity a chance to build shit there, alongside heating the planet and thicken the martian atmosphere a 15% more.
the lack of pressure wouldn't be so severe and make things better in the long run for any future martian colony.