I’ve seen much worse, and I’m far more worried about the quality of the actual film itself than the color fade. Also I’ve never seen a full print of the original Planet of the Apes. Only people selling an incomplete version with a few reels, and other Planet of the Apes films. Do you have an archived link to the sale of that print?
It may be too badly faded for the color to recover even with the best possible scan. Even the best scanners in the world cannot cannot get full color separation because it’s just not possible with today’s technology. This is what the spectrum looks like with unfaded film:
Once that yellow peak has faded below magenta it can’t come back, not at the moment anyway and quite possibly never.
Lots of faded films can still scan though and recover good color, it just all depends on the extent of the fade.
And yes I can show you the ad send me a private message.