Hi Cindy, here's the PSD.
I've used simple Solid Color layer where you will use a Gradient layer instead, but importantly, I want you to see the Levels layer.
So far so good.
The question is, should we remove the texture from the parts of the blanket where it's visible? I mean, do you feel it's too obvious that there are some textured parts and some not?
Ok, can you open one of the photos that shows banding, and go to Edit>Assign Profile, and assign the monitor profile to the image, and tell me if that makes it better, or worse, or the same.
Use the eyedropper, like this, to match the dark section to the light section - roughly match, at least.
Then it's the normal matter of using a gradient layer to replace the whole background.
Have you found another photo with a suitable bit of toe for swapping?
In what way is this one different? May I see one of the other photos on which you did it successfully?
This is the best I can offer. It's not perfect, but an improvement to a degree, at least.
First, a fabric-coloured Solid Color layer on Lighten mode, and paint gently (10% brush) over the darkest areas. Then the Hue/Sat layer over the top.