Plot hole: In the Bendwater escape, the security cameras show the time outside the prison as 15:59, but a few cuts later, there's a shot of Stallone in his cell with the timecode being 15:56. That's not a continuity mistake, since it turns out that Breslin rolled back the security monitor, the problem is, he is shown doing that at 15:57, and barely rolling the tape past the point when he stands up. By the time the guards are looking at the monitor after 16:01, the tape showing him nice and quiet 3 minutes before would have already rolled to the incriminating part where he breaks out of the cell. (00:06:50 - 00:13:25)
Other mistake: After the Doc looks in the book that Breslin told him to, he tells the guards to go get him. He says to go get Breslin from A Block, however the subtitles say E Block. Breslin was moved to E Block and then moved back to A Block after he negotiated with Hobbs. But the Doc says A when the subtitles say E. (01:20:05)
Factual error: When Ray figures out he is on the ship, he makes it back to his cell, creating a flood along the way, he then swims through a lot of water. When he returns to his water drenched cell and escapes with Victor, his clothes are bone dry. (01:54:30 - 01:55:20)
Plot hole: The Tomb is supposed to be a top-secret off the grid prison that nobody is supposed to know about yet the schematics for the place are conveniently left available online such that a hacker can search for it with no problem, on top of that the fact that it's known on the outside world as "The Tomb" suggests it's more well-known to people that it should be.
Plot hole: Breslin is supposed to going to an off the grid prison, a place nobody is supposed to know about outside of the prison except for Clark, who is the only one who really knew where Breslin was being sent. So why in the world would there be a warden as the "contact on site" that Breslin would inform if things didn't go well? It also makes no sense that Breslin would have an evacuation code when his own people have absolutely no idea where in the world he could possibly be.
Plot hole: In this top level state-of-the-art security prison with transparent walls, cameras everywhere and no civil rights concerns since it's all illegal, there's not a single hidden microphone in the communal parts. Even worse, the wardens never search the inmates, who can smuggle freely all sort of stuff, sometimes in the most blatant way (like when the protagonist gets stitches for his leg).