I would second the comments of @foosondaughter. We visited both places with our D who has no interest at all in Greek Life. We felt that Greek Life at Davidson was not overwhelming in any way and that D would be completely comfortable there, despite her disinterest in Greek Life.
With respect to Grinnell, I loved that school (as I did Davidson) but I just couldn’t get D to look past the endless cornfields outside of town. As a life-long resident of CO, the very rural, flat environs around Grinnell was just too big of a change for D.