Power Steering Pump A4 8E

I have an Audi A4 8E AVB, manufactured in 2002.

The customer applied full brakes, and then the brake pedal got stuck in the down position.
We loosened the bleed screws so we could push the car.
Now I have removed the power brake booster.
"When I turn the brake booster upside down, a mixture of water and rust (a brown liquid) comes out of all the openings."

Where is the water coming from? Should I also replace the tandem pump?

It's definitely not brake fluid; it's not greasy, and the car has never had any brake fluid leaks.

He probably used to have a significant amount of money in his bank account.

Common problem with 8D, 8E, 4B, 3B models, etc.

Okay, let's check right away if the water outlets in the water tank are clear; if necessary, remove the rubber stoppers from the outlets.

I already took the rubber bands off.

By the way, the actuation bolt on the brake booster is bent.