@Floridian Have the green marks changed at all? Are there any more appearing on the other flowers, or more on that flower?
I went back and looked at the pictures closely again. In your pictures it's only the one flower that has the green marks, so it's not a disease and probably not insects either. The damage would be more random and widespread.
It looks like those two petals/sepals may have been folded together before the flower opened, and maybe they got bumped (bruised) or otherwise damaged to cause the green color there.
The rest of the flowers look perfect, and the plant looks healthy.
