In New Orleans, the eccentric owner of a floating casino plays both sides of the law– providing law enforcement with sensitive information while systematically eliminating threats to his growing criminal enterprise.
The logline sets up more of a situation than a plot.
As a result of playing both sides, what specific dramatic problem arises? Who is the antagonist that creates the dramatic problem, who threatens the protagonist? What must the protagonist do about it?
What DPG said but also the wording of the logline lacks economy.
Better to describe less elements more accurately than more elements vaguely, for example:
“…a floating casino…” = casino, unless it being a floating establishment is critical to the plot casino will do.
“…eccentric owner…” = owner, eccentric doesn’t read as a good character flaw in this instance which makes this character description redundant for a logline. Only describe what it is about the MC that is important for a reader to know.
What kind of character description will make it harder for the MC to achieve the goal? (but as mentioned we don’t know what the goal is from the logline…).
“…providing law enforcement with sensitive information while systematically eliminating threats…” = rats on his enemies, criminals ratting on their enemies to the police is a well established trope you can use it in a logline to help with economy and clarity.
Hope this helps.