On the second play through, you can find the Obsidian Goblet in the broken glass display in the middle of this room. Grab it to earn the Unholy Grail achievement / trophy.
Head through the hole in the wall and walk down the long steps. It’ll seem like forever, but you’ll eventually reach the bottom. Go through the door to the next room.
This next room is pretty small. Grab the First-Aid Kit on the table and head through the next door.
This area has a short hall way and a few rooms connected to it. There will be a few Straight Jackets in the hall, so be prepared. Take a left into the hall and enter the door on the right. Inside are a few more portraits and a box of Handgun Bullets.
Reach the last door at the end of the hall to find a dark pit in the middle of the room. Investigate it and jump down.
Once you reach the bottom of the hole, you’ll realize you’re inside of a well. A brick wall circles you. Investigate the walls until you reach a spot that’s different from the others. Equip the Steel Pipe and hit the wall until it breaks, exposing a door.
Enter the door to find another small hallway with Straight Jackets inside. Continue through here until you reach two doors. Go through the door on the right, it will be the only one unlocked. Walk through the next door on the right to find a small carpeted room. Grab the Spiral-Writing Key on the floor and your light will go out. Use the Dry Cell Battery you got from the hospital to turn it back on. You should immediately notice Beetles on all the walls of the room. The door will be locked, but there will be an electronic keypad to the right of the door. Investigate it and you’ll notice a few of the buttons are highlighted. Guess at the code and it will ding if you got it right. If you get it wrong, it will buzz. Possible solutions are: 1-8-2, 8-1-5, and 3-1-9.
Walk into the next room at the end of the hall to find a steel door on the floor. Use the Spiral-Writing Key you just got to unlock the door. Jump down this hole to continue to Toluca Prison.