The stupidity is knee deep though. The way they have been clearing the prison wants to make me claw my own eyes out.
If I was there I would have cleared the outer courtyard by stabbing them through the fence, saving ammo. I would do the same to the inner courtyard, make a lot of noise until they come to the fence then stab them, if needed, send the Asian kid in to run around screaming getting any stays to follow him back to the fence. Once secure grab all the bodies and take them out of the compound and away from where they might pollute the river or ground.
Once everyone is rested and settled a bit, secure one area inside the prison where they can lock themselves in for safety. Then proceed to throw open doors yelling and banging and seeing if anything comes to you, slowly clearing areas one at a time.
Hell if they were really ambitious they could have gotten the walkers from the inner area of the prison to follow a person acting as bait and trap them between the inner and outer fence as a sort of extra guard. That way if any other living people come by they see the walkers and carry on thinking the place is infested.
The prison is an ideal base of operations, they can plant food, store goods, place watches in the towers, maybe even take a few people in to help with the place.