Your harp is tuned right.
The 1-2-3 blow has to be lower than the 1-2-3 draw. I guess Mitch is playing a 2-3-4 blow instead. Both blows are C major chords.
Up to and including hole 6 the blow note is always lower than the draw note on the same hole.
From hole 7 on the blow note is higher than the draw note.