It’s not so much the motivations of the ‘would be assassin’ or the identity that should be her goal, rather her end game is to catch the person so they don’t try it again. This should be specifically described in the logline as her goal.

On a separate note, a little pet peeve of mine (other’s opinions may vary) is the use of too many adjectives in a logline.

The goal of a logline is to present story elements that on their own mean little but when combined together mean a lot. A naive farm boy who wants to defeat a galactic empire works so well because the odds are stacked so heavily against the MC. There was no need to describe the MC as helpless, poor, or under-resourced and the empire as known for its merciless nature:
After the evil galactic empire kills his family, a naive farm boy must learn to become a Jedi night in order to defeat their army and free the galaxy.

Now with too many adjectives:
After the notorious evil galactic empire kills his loving adopted parents, a poor and naive farm boy must become one of the mysterious Jedi nights in order to defeat their army and free the enslaved galaxy.

You’ll do far better expressing a lot of story information with fewer adjectives than with more.

Here is your logline stripped of redundant adjectives and descriptions:
After an attempt on her life, a misanthrope mathematician must team up with her savior to catch the would-be assassin.

Consider restructuring the logline so it starts with the inciting incident and finishes on a clear goal. You describe the MC’s descovariesin the story but not the MC’s actions and goals.

Also, posibilities should be left out of a logline – either it was an inside job or it wasn’t. Best to be more definitive with story elements in a logline than indicative.

For example:
After his partner is killed, a detective uncovers a plot by dirty cops and must prove their guilt to stop another murder.