EA Games, the developer of NFSMW, was quick to respond to the issue. The company's community manager, Alex, posted an apology on the game's official forums, assuring players that a fix was being worked on.
If you prefer not to use mods, you can try adjusting how Windows handles the game. This is the "old school" fix for the Blacklist bug. Right-click speed.exe and select . nfsmw blacklist defeated bug fix patched
The easiest console method: Download a "100% completed save" that has the BMW M3 GTR already unlocked. It bypasses the bug entirely. EA Games, the developer of NFSMW, was quick
: You can still progress by driving to the star icon on the map in free roam to manually start the boss race, even if the menu says they are defeated. This is the "old school" fix for the Blacklist bug
: If you proceed with a bugged save, you will not receive the BMW M3 GTR at the end of the game.
On consoles, the bug was linked to the game's memory allocation. After 3-4 hours of continuous play, the console's RAM would fragment. Defeating a Blacklist boss requires loading a unique crowd model, opponent car wreck, and cinematic. If the memory was too fragmented to allocate for these assets, the game would soft-lock. This is why the bug seemed to appear more often on Friday night marathon sessions than short playthroughs.