Maybe I misunderstood but I think Louie meant that she accepted that guy's invitation to go out, and so Danielle's seeing someone. Then again...maybe not.
If not then yeah, what Ryan said...go with the one you like more, why be scared to go for it? If she's seeing someone, fair enough, but if she's not...go for it.
(I initially misread what Louie had said and thought he'd said the girl was going out with someone now.)