It worked. He navigated the menus, selecting "Expert Mode." He began manually typing in 16-digit hexadecimal codes he’d scribbled on a napkin: 0E3C-7122-6A1B 10B2-9F01-0000

Please be aware that:

For many modern players, using the ISO with the PCSX2 emulator is the most convenient method. PCSX2 Ultimate Guide - Activating Cheats!!!

Depending on your setup, there are two primary ways to use this ISO: on a real PS2 console (using OPL or ESR) or on a PC (using PCSX2).