Here's the method I used which I think is the quickest:
Start or continue a game on center perks or the prison of your choice. Get your int to 60 and collect the following items:
battery x 2
1st craft an energy module from battery x 2 and wire, then craft makeshift stun gun from energy module, paper clip and duct tape.
Now equip the stun gun and wait for a time when there are a bunch of guards/inmates in one place such as roll call or meal time and quit and save your game.
Load up you game and quickly zap the guards/prisoners with the gun until you run out of shots and then hit guide button, highlight The Escapists 2 and hit the menu button and quit out before the game autosaves. Load the game back up and rinse and repeat.
The stun gun only has 5 shots but it will OHKO inmates and normal guards. Plus it can knock out multiple with a single shot if they are close enough together.