Generally, 9th chords are in root position. Can you redistribute to put some of the notes in the RH with the melody? What chord tone is the melody? If you're going to leave out a note, generally only the 5th can be left out without compromising the chord quality.
Note quite sure what chord tone means...
But the song's key signature is no flats, no sharps.
The accompaniment progression (indicated chords) is...
|: C7, F7, C7, F7, C, Ab7, Bb9, A9, D7, G9 :|
at the part where the Bb9 , A9 comes in... (the topic of this post) there's written chords under each of them on the staff.
Ab.D.C.E (all together) is written on the staff under Bb9 , and..
G.C#.B.E (together) is written on the staff under A9
the Bb9 , A9 part of the song is just a little added drama, I believe.
Also, I thought the song sounded as though it were a Blues Scale.
I hope this is enough info for a wickid answer.