I didn't encountered any error though.
you can use the Japanese files to cross that point and then create a save if necessary and then use the English patch again.
And this error isn't the same like that you encountered before.
I know what you're saying, because it has worked for me with other games.
In this case, I deleted the old saves, and used the Japanese files (from that point, and also starting a new game). I did this with and without an emulator. That is, I did 4 tests.
I have the same error again
As we would say in my country, "my papers have been burned"