most jails have system to record your cell checks and counts Could be as simple as a slip of paper at the end of the tier or hall with your initials and the time on it.
So if you sign you checked at 3:15 am and the corner says the guy died 12-1 AM you’re up shit creek if they find the body at 4:15.
Like I said in my previous post, my facility had guard-pass systems. They consisted of RFID chips bolted to the walls at certain locations of the cell block. You had a wand that you had to physically touch to the chip to record your round. In segregation there was a chip for each and every cell. At the end of your shift, you downloaded your wand to the control center computer just before shift change. Not much of a way to game the system on this. If something happens to a prisoner, and the wand and the camera footage don’t support your logged rounds, you’re toast.
CC