She probably could, but if she was doing the math her options were limited. She could perhaps get out. What then though. Her existence would either be reduced to forever running and never being sure where her enemies were would make her existence miserable to unbearable or she could beg her way back into Dalinar's good graces. I'm not sure that either of these options would work for her. I read her parts and I see in her a most Roman sensibility her pride might just prevent her from relying on charity or living in fear of dying at an assassin's hand.
Maybe, but it is just possible that she was about out of moves. Her resources are possibly at their limit or gone, she is being pursued by master assassins. At this point she has one last chance to mess with her enemies while going out on her terms.