YEEEES! It worked! There was a weird .DAT file in the file you provided that gave corrupted data but when I removed that file it worked like a charm, thanks you ever so much man!
I've been trying a bit myself with Bruteforce save data tool but I couldn't get it to work. The specific required key file for Ninja gaiden sigma (for updating account id) wasn't in the database and I trying to bruteforce that seemed to take forever on my computer.
How did you actually manage to do this,if you don't mind me asking and if you have the time to explain? I totally understand if you don't.
Super-grateful for this anyway!