I wouldn't worry about it too much Forever.
The reason the two versions are an octave apart, is because one set of notation is designed for someone to sing, and the other is for a computer to play. It's standard practice for vocal notation to be written an octave higher than how it is actually sung, for ease of notation.
So, the notes from your MIDI file are technically
the exact notes that Fred sings. But the notation from your PVG score uses the correct way to notate the vocal line.
I would say the more artistically correct version to use would be the PVG score version.
Whatever you do though, make sure that your artist puts the Eb key signature in the staff is he uses the PVG version, otherwise the notes will be incorrect.
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