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.

The story elements in this logline are fragment and as a result the plot is unclear.

Just to clarify.

Main character: a former sheriff

Inciting incident: he is kidnapped

Goal: to be rescued

The main character action: leaving joker cards for an agent

I think the problem here may be with the concept and character. If he is a former sheriff presumably he can put up a fight and wouldn’t be easy to kidnap, is he injured and therefore can’t fight back? How could someone just kidnap a former sheriff?

Once kidnapped why would the sheriff comply with the demands of the perpetrator? Can’t he just refuse to do anything? Are his morals being challenged doesn’t want to break a promise to a former friend but doesn’t want to break the law (this is eluded to but not described as his central dilemma)?

Leaving cards for someone else to find is not a compelling enough an action to satisfy a whole act 2 of a film. What else can he do to help him self that would be more interesting for an audience or more importantly for a reader?

Lastly the main character’s problem is a grown man getting away from a kidnaper (no immediate threats have been described) this is not a story worthy problem on its own. Can you add a personal aspect to this? Or make it a must achieve goal or else? Perhaps a ticking time bomb of sorts?

Hope this helps.