One could use a spectroscope to record that the reflected light has a frequency of 700 nanometers. In such a case, "light" would be akin to sound in the tree/falling/in the forest. However, the "color" red arises from the physical phenomena of visible light interacting with the cones of the human eye with the mind processing the interaction. While the wavelength of the light itself may exist, the color does not exist without the observation of the eye.
Aside from the details of the perceiving mechanisms between hearing and vision, I don't see where your distinction lies.
When one refers to "light" one is generally referring to that part of the electromagnetic spectrum that is perceivable through vision to the human eye. That "light" occurs in a range between 380 and 740 nm, with violet occurring between 380 and 450 nm ± and red occurring around 620 and 740 nm ±. The human eye can perceive differences within that range. In physics "light" sometimes refers to electromagnetic energy of any wavelength, for the purposes of this discussion, however, let's stick with that part of the EM spectrum that is perceivable by the human eye.
Humans perceive light throughout its entire spectrum through the mechanisms of their eyes.
Humans perceive sound through the mechanisms of their ears.
In exactly the same way you assert that "color does not exist without the observation of the eye," sound does not exist without the observation (i.e. perception) of the ear.