--- By analyzing a memory snapshot from the flycast emulator, I found that the buffer at 8cfffb34 holds the visible portion of the initials you type in. But if you keep typing, the characters you put in before get pushed into the buffer at 8c3abf18.
After loading the memory snapshot into Ghidra, I found that the function at 8c0334d8 reads this buffer. It performs a transformation on the buffer and then checks whether the transformed value is a list of six special ones. ---
How?
I don't know exactly how flycast works but I've done similar things with other emulators and you take an action in the game (take damage, type something), then search memory for that value. In this case the ascii code for the letter typed. Keep doing this until you've narrowed down a single block of memory that holds everything you've done