Thanks, Rikki:
No doubt in my mind that Zuki has written an original song even if an Arranger was used. Chords and notes in the "body" of the song must be played and the Intro and Outro are like "icing on the cake"... especially if they are striking musically and lend credence to the genre of the song. Don't forget, the voices/instruments selected for the song's style can really make a difference.
Nearly every song I've written began with an idea, led me to a notebook to write down the story-line and to later, fill in the chords for each verse, chorus or other elements of the song. Style selection is a bit like an Easter-Egg hunt and I do my best to find ways to not use styles used on earlier songs. If that isn't an option, I modify the style to suit the song... or resort to using a minor key theme for the work... if that is appropriate.
If money grew on trees... I would hire a demo house to do every one of my songs... but being broke and sitting on the side of the street with a tin cup is not what I'm seeking... LOL!
Keep on "keeping on" Zuki! It's okay.
All the best, ----Dave