The colors of white that people think have a "blue undertone" usually belong to the green-yellow hue family and the discernible hue they're perceiving is likely more greenish than bluish but they assume it's blue because they never imagine that all colors of white belong to a hue family and very few belong to the blue hue family.
There are very few colors of white (I know of 1) that belong to the blue hue family because color measurement instruments have trouble measuring low chroma colors in the blue region of the spectrum.
If you can't measure it, you can't make it. As a result, white paint colors from the blue hue family are practically non existent in commercial paint brands. It's science.
When you know what to look for - greenishness - and then see it, you can't unsee it.
And that is often the case with Decorator's White. It belongs to the green-yellow hue family. Like I said, most whites from most brands belong to the yellow to green-yellow hue family neighborhood as you can see in this infographic.
What makes them look "just white", off-white, creamy or ivory is the amount of discernible hue also known as Chroma.
Decorator's White has a Chroma of 0.20 - that's not a lot.
Chantilly Lace has a Chroma of 0.27 and it's not that much different from Decorator's White.
Tho it seems counter intuitive, I don't think Decorator's White has enough Chroma for you. I think you need more colorfulness to work with the light you have to work with.
I would grab chips of PPG's Delicate White, SW's Extra White and BenM's Snowfall White and see how they compare to Decorator's White in your space.
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Floor and wall tile
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