Color laser prints one horizontal dusty line across sheet. What hits the sheet only once?

[Color]

Oki C3200 makes a fuzzy line horizontally across the sheet (8.5" wide), 1/3 down (11" direction).
I dusted a drum with a soft paintbrush, but It seems like the small diameter of the drums would contact the paper several times per pass.
What component contacts the paper in only one place? What could make this singular mark?
Thank you

 

[Color]

Am I right in thinking that if there was damage across a drum that it would print more than one on a sheet, because the small diameter of the image drum? Also the fuser roller, if it had a scratch across it, it would make the paper more than once.