If all else fails and you have a DAW a workaround is put the MIDI drum track in your DAW and put each drum on it own track. Some DAWs can do this automatically while in others you must copy the drum kit many times and delete the drums you do not want on each track. Since you know what MIDI notes you have to change You can copy the drum track 3 times. In the three copied tracks delete all but the note you want to change and then change it to the correct note. After that is done then delete the three notes in the original track and merge all four tracks. You may have to input the entire song in your DAW prior to doing this if your Yamaha can input only one MIDI file at a time.

I know this is a PITA but it works.

Whenever I get something stuck in the back of my throat, I dislodge it by drinking a beer.
It's called the Heineken Maneuver.

64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware