Transferring Save from PS3 to RPCS3

In your Save folder, try delete your PARAM.PFD file after you've decrypted the save. Then try loading it in the game. I believe games are attempting some kinda profile verification with the PFD as it contains all the user profile signatures and keys associated with your Playstation 3 console. (Which is also why using other people's saves doesn't work often on the PS3.) The SFO file just provides information about the save file that you see over the thumbnail when viewing it on the console.

Last week, I copied my save from Project DIVA F 2nd to my PC and it worked just fine once I removed the PFD file and left the actual save decrypted.