I'm just trying to get up a reputation for dark matters goons to tell him. If dark matter hears someone grabbed serenity in one swoop even with the other titans there, then he would definitely be interested. Also I think that he should grab her and get away but the evac doesn't get to him in time and the titans manage to rescue her. I think that's a good start.

And they would be able to tell if they got a blood sample. Or cross referenced her abilities with their data base. However, they don't have all the facts on her yet.