Is this method different to the one here?
It mentioned that you also need to do this:
Edit the PARAM.SFO of the game to ask for 3.41 instead of 3.42
Replace the EBOOT.bin file from Medal of Honor with the one from UFC 2010
Install OM 2.1, press start to direct the patch to install the game data into your external drive
Once you run the game it will ask for game update 1.01, install and your ready to go."