If you just used the graphics, and did not reproduce a real news broadcast, that is not copyright infringement. An analysis of fair use is not necessary. Hypothetically they filed an improper DMCA takedown notice and are now liable to you for damages. But you should have an attorney confirm this.
But that does not mean you can use their graphics, as it might be trademark infringement or something else.
Remove the infringing logo from your video and any reference to KRGV and you should be fine.
Was the film a product of your studies? Was it supervised by the professor? Why was it uploaded? why did it require 40 seconds? why did you need a real, as compared to fictional, TV station logos?
You need to have a copyright attorney review the details and conduct a fair use analysis before serious advice can be provided.
If the video was taken down, but you did not receive a demand for compensation, then why would you like it uploaded again? Have you though of replacing the logo with a fictional logo?
Talk with an attorney, in your profession you will need one frequently.
USPTO Registered Patent Attorney, Master of Intellectual Property law, MBA I am neither your attorney, nor my answers or comments in AVVO.com create an attorney-client relationship with you. You may accept or disregard my free advice in AVVO.com at your own risk. I am a Patent Attorney, admitted to the USPTO and to the Florida Bar.
This is not a copyright issue, it is a trademark issue. unfortunately, when you used the station's call letters, you used their trademark as well. There is no fair use in this regard for a trademark. Your film incorrectly attributed a newscast to that television station that they did not produce. It is understandable they would not like this. It is possible they might have granted permission under certain circumstances, had you contacted them before the fact. But now, that likelihood is greatly reduced. You will need to remake your film and change those call letters. It would also be well - if the graphics you used look just like their's, that you also change the graphics in some way.