The exact function of the MC in her work place in this logline adds words that don’t contribute to the readers understanding of the plot. I would change her description to: “a headstrong scientist” and remove: “…developing microchips implanted in the brains of test animals …”.

“…fears that she might be a subject…” is she or isn’t she a subject? In the military as in story one is taught to react to clear and immanent danger not the fear of it. Better to specify the actual danger she is in and forcing her to take action.

Also what is the inciting incident? Why does she now fear she is in an experiment?

Hope this helps.

As mentioned above less is more you have an action packed compelling premise here but you just need to trim the logline down to deliver the sense of urgency.

“Plebe year just got worse for…” sounds like a marketing hook no need for it in the logline.

“…in retaliation for his normalizing relations with Cuba…” in this instance the antagonists motivation is not necessary, let an assassin be an assassin and do what he or she does in your story.

“…It isn?t until minutes before the killing is to begin…” could be changed into “…hours before…” give your film a plausible scope otherwise you would be stretching a few minutes into 2 hours.

“…from succeeding.” redundant stopping the assassins implies this.

Reserve the wordy and colourful descriptions for the synopsis or treatment and use only the crucial elements of the story in the logline.

my try:
When two military cadets discover a plot to assassinate the president they have two hours to stop the killers.

I would also add that it would be great if you could add in an obstacle or character flaw for your main characters. This is a dual protagonist plot and that also needs attention and justification, why are there two and not one cadet? Why is the story about two main characters more interesting than one? Are they brothers, twins, owe a blood debt to each other?

Hope this helps.