Welcome to the Hell named Paint! Your problem is it's definition.

That could very well be Believable Buff. Colors change in different lighting and sometimes just the orientation of the light. If this is a pro-photo, as it seems to be, it will also be "processed" and the color you see is in fact different. When we all look at even the same color over the internet, we are rarely actually seeing the same color - monitors are just that different from each other in how they portray color. That's why questions like yours are difficult to answer. The color they used may not be the color you need to produce the same effect as shown in the photo you're looking at.

I am repainting with SW Steamed Milk. I put a test patch on a wall, stood in the same room with the same lighting a few feet from the wall, held the chip in my hand and swore it was a different color. Walked the chip up to the test patch and it was the same. Color can vary by time of day and location in the room.

Start by getting chips. Get chips for Believable Buff, Honied White and Vanillin and anything else that feels like that photo. If you are at a SW store, they will let you sign out an entire fan deck. For you to be sure that any color you pick ends up looking like the the photo when it's in your room, you'll need a tester - either those printed color sheets or a small sample of the actual paint. Choose the closest two or three chips and get the printed color sheets or their small sample cans of actual paint. Always choose from the actual paint and with your actual lighting. That means the daylight in the actual room and the color temperature of the lights you're going to install.

You can adjust any paint color by tinting it. If it's just a little dark or a little light, SW can change the proportions of color added to make it more or less intense.

Also, Tessa Skeens at this web site is a consultant who might be able to help you as it's a color she's very familiar with.