The cover art was changed because it was not an accurate depiction of the game, just like every other aspect of the game was changed or influenced based on feedback. No distributors were involved that I know of, and there was only small website that said they didn't want to preview the game if it meant displaying the original artwork.
Larian does read the forum. If you have a day free next week, though, you can see if there are any EE playtesting slots open:
Wanted: Fearless Source Hunters near Ghent, Belgium
