cannot see the ceiling color. you need to take pictures with better lighting

It is near impossible to tell what is off based on photos.

It could be a warm/cool issue - your wallpaper may be cool but you chose a warm greige for the ceiling (or vice versa). If that is the case repainting the ceiling a cool (or warm) greige may fix what you think is off.

I would resist the white ceiling. It looks like you have a nice powder room there with a bit of drama. You don't need to dumb it down.

Good luck!

Here is another photo. The ceiling color is Stonehenge greige- thought it looked the same as the greige in the wallpaper but now that it's up - it looked more taupe. I wonder if a color match could be done from the wallpaper greige even though it's such a small area.

Do you you have a leftover piece of the wallpaper? If you do, you can take it to a reputable dealer who should be able to mix the matching colour for you.

I agree with your instinct that you should use that colour for the ceiling.

9 feet is high enough to do a color. you can tell already if you have the correct strength of color, if when you sit down you don't feel oppressed by the ceiling. make sure your new color pick is the same intensity. good luck, it's pretty from here.