Keys live in the bytes Evidence before conjecture — every jump, check, and key mapped where they live in the disassembly.

0x00401000  push   ebp                      ; prologue
0x00401001  mov    ebp, esp
0x00401003  sub    esp, 0x40                ; local buffer
0x00401006  xor    eax, eax
0x00401008  loc_check:
0x00401008  cmp    dword [ebp-4], 0xDEAD  ; key validation
0x0040100F  jnz    loc_fail                  ; → bad boy
0x00401011  lea    eax, [msg_success]        ; → "Unlocked"
0x00401017  call   puts