My prayers have been answered! Where was this when I looking for this?
Update:-
Tried different methods to copy but didn't work, then I tried this:-
Copy your 'Original save to USB 2', then copy the entire Yoh/Platinum save above through the usual PS3 XMB method (using the retail Operating System), then go to Multiman, plug in USB 2 and copy ONLY the PARAM.SFO file OVER the SFO that already exists on your PS3. So basically, you're only copying YOUR SFO file to the Yoh save that's on your PS3 already.
Once done, it'll show Atilla's name, and then as it loads, it will magically change to yours and work without corruption
So in short, copy your save to a usb, and from a seperate USB copy the 'COMPLETED' save onto your PS3, then go to Multiman and copy ONLY your SFO file, from the USB, to the 'COMPLETED' saves folder on the PS3.
I repeated to make it clear to myself, as I know I will soon forget this ish myself..