Was just looking through one of my referances and realised i was mistaken, i do know a German aircrfat with one colour on the wings, the He 162. A bit dumb of me really seeing as i will soon be building two. I was looking through one book which has the same images and captions as the link you posted. It does seem KG 54 had a mix with some aircraft have two colours along the top of the fuselage and otehr haveing one, which in itself was unusual. There are some better pics of otehr aircrfat which do appear to have one colour on top of the wing.
Given the late stage of the war, and the desperate situation, this would make sense, so i would say it was not the case.
Go with what you think is right. Inless you have a pic of the aircrfat your doing showing the top of the wing, you just can't be certain. I doubt the makers of the decals know for sure, chance is they just took a guess.
I am a Norfolk man and i glory in being so
On the bench: Airfix 1/72nd Harrier GR.3/Fujimi 1/72nd Ju 87D-3