Freedom of Information Act only applies to the federal Executive Branch. Both Congress and the Judiciary are exempted from the statute by the statute.
That isn’t to say there aren’t avenues available to interested parties - like journalists - to unseal sealed court records. But, those avenues don’t include FOIA.
States, OTOH, often do have sunshine laws that give a good deal of people to John Q Public to uncover evidentiary materials that may or may not have been used in a criminal case, like your Columbine videos.
But it is suppressed evidence from the trial. The trial is about those tapes. Is Planned Parenthood claiming trade secrets on those tape?
Even with the trade secrets claim the church of Scientology found that the alien story got leaked to the public through court papers.