Here are some of my thoughts Ofer:
1. Are you being blamed for this issue? If not: There are better things you can do with your resources of time and treasure than trying to fix something like this. In my experience, mystery color loss issues like this are maddening, nearly impossible to diagnose, and even less likely correctable.
If you are being blamed, or if you cannot resist the challenge, read on:
2. Are the cushions down filled? Any time I see mystery color loss or color gain in an irregular fashion like that on a celluose fiber fabric, I think flame retardent in the ticking. Even if there are no feathers, some upholsterers and some furniture manufacturers use the flame retardent ticking on furniture that doesn't use down, just because its paid for inventory on hand. The quality control and concern for ongoing performance in furniture manufacturing is primitive in comparison to carpet manufacturing.
3.a. Is this really color loss? I know this one is a stretch, but compare the lighter spots to areas of the fabric that have never been exposed to usage or open air. In some VERY rare cases, fabric protector is splattered or unevenly applied, and you end up revealing cleaner areas, not bleached areas. The shape of the spots lead me away from that possibility, but its good to get that one out of the way. I have seen this more in the pattern of a fan spray or big blotches from a trigger sprayer, but who knows?
3.b. Is it really color loss? Protein based spills sometimes "dry white". The baby formula scenario is possible, but those spots don't have the "crusty film" look to them. What happens if you gently scratch them? Formula should look "chalky" when scratched.
4. "The Butler Did It": In this case, the house keeper may be at fault. I have seen spotters used by cleaners that are usually considered to be safe on textiles cause this sort of color loss. If the house keeper intentially or unintentionally sprayed some cleaning product on the cushion, it could reveal itself after extraction cleaning as color loss in these areas.
5. The Bottom Line: If you aren't being blamed for this, walk away. If you are, I see little that can be done to fix this, unless it really is a lighter colored residue. If this is an extraordinarily expensive piece and it looks like you are going to "go down with the ship", call me. What I'll tell you I won't want to put in print here.
