Except the cameras didn't malfunction. There's video of the cell block that shows an empty hallway. Now, there's no video of inside the cells due to privacy concerns. There's never cameras that show the inside of cells. This privacy feature has been turned into a "There's no video from the cell because of broken cameras" by conspiracy nutjobs who don't actually know anything.
As to the guards sleeping or playing on their phones... There were only two for that section of the prison, and they had been sleeping or otherwise faking their rounds for weeks, if not months. The video evidence from the cell block is how they were caught.
Epstein had been specifically pulled off suicide watch, even after attempting suicide previously. That's the part that's sketchy. He also had a visit from his lawyer a few days before where he changed his will to fuck over his victims.
But no, idiot meme lords think some shadowy government figures came in and killed him without leaving any evidence of existing.
I've read actual accounts of things the CIA does, and they wish they were even half as competent as the nutjobs make them out to be. Remember, these are the same people who used "pizza" as a code word in Lebanon to mean, "go to the Pizza Hut for more orders", and then let Hezbollah sit and watch about a dozen agents and informants meeting at Pizza Hut.