Actually, you are making perfect sense and are describing a natural occurrence to the bill and coloring around the eye. The beak scratches may appear as red or other discriminating marks highlighting a usual fight with another swan or bumping into something and receiving a scratch. Eventually, the scratch will heal and the normal coloring of reddish/orange will reappear.

The dried out coloring of the black area around the eye can be several reasons. One, the bird is older and is losing some of its coloration, two, the fading color is occurring due to the moulting of the feathers around the eye, or three, the bird is somewhat dehydrated, especially if there has been very hot humid temperatures. Normally, the black coloration will return after the molt and the swan becomes more hydrated. The Regal Swan